Method for selecting blood specimen having possibility of including blood coagulation abnormality

Abstract

The present invention is a method for selecting a blood specimen that may have a coagulation abnormality, comprising: acquiring Ys(X) for a blood specimen under examination, wherein the blood specimen under examination is a blood specimen for which prolongation of APTT cannot be determined with certainty, and Ys(X) is a ratio (%) of Rs(i) to Rmax_s at a measurement point or time at which Vs(i) reaches X% of Vmax_s. Rs(i) is a coagulation reaction curve of the specimen, Vs(i) is a first derivative curve of Rs(i), Rmax_s is the maximum value of Rs(i), Vmax_s is the maximum value of Vs(i), VmaxT_s is a measurement point or time at which Vs(i) reaches Vmax_s, i is a measurement point or time, and X is a variable and X > 0. If the measurement point or time at which Vs(i) reaches X% of Vmax_s is after VmaxT_s, Ys(X) is defined as Ys(200 - X).

Description

Method for selecting blood samples that may have blood coagulation disorders

[0001] The present invention relates to a method for selecting blood samples that may have a blood coagulation disorder from among blood samples that do not show a clear prolongation of the coagulation time.

[0002] The activated partial thromboplastin time (APTT) is used for screening intrinsic blood coagulation reactions and preoperative testing. Patients with prolonged APTT are considered to have some kind of abnormality in blood coagulation function and are at risk for bleeding if prolongation due to errors in blood collection or centrifugation procedures, the effects of administered drugs, or thrombus origin is ruled out. However, among samples from patients with mild hemophilia or other coagulation disorders, there are cases where the APTT is not clearly prolonged, but is within the normal range or slightly prolonged beyond the normal range. Furthermore, the sensitivity of APTT to each coagulation disorder factor, such as coagulation factors, heparin, or coagulation factor inhibitors, can vary depending on the assay reagent. Therefore, APTT screening, such as preoperative testing, may miss patients at risk for bleeding.

[0003] Patent Documents 1 to 4 describe the calculation of parameters such as weighted average time, weighted average height, peak width, and baseline length of the coagulation rate curve of a blood sample, and the use of these parameters to estimate factors that prolong blood coagulation time and evaluate coagulation factor deficiency. Patent Documents 5 and 6 describe the calculation of a function T(X) that represents the measurement point or time at which the coagulation reaction curve reaches X% of the maximum value, and the estimation of factors that prolong the coagulation time of the test blood sample based on T(X). Patent Document 7 describes the calculation of a function T(X) that represents the measurement point or time at which the coagulation rate curve reaches X% of the maximum value before and after the point at which the coagulation rate curve reaches the maximum value, and the estimation of factors that prolong the coagulation time of the test blood sample based on T(X). k Point p where k and q k Calculate the p k and q k It is described that parameters for estimating blood coagulation abnormality factors are calculated using the above method.

[0004] International Publication No. 2020 / 101025 International Publication No. 2020 / 158948 International Publication No. 2020 / 218425 International Publication No. 2021 / 177452 International Publication No. 2022 / 186381 International Publication No. 2023 / 032978 International Publication No. 2022 / 054819

[0005] It is desirable to prevent overlooking samples from patients with blood coagulation disorders who do not show a clear prolongation of the clotting time in APTT measurements.

[0006] The inventors have found that even when blood samples from patients with blood coagulation disorders do not show a clear prolongation of the clotting time in APTT measurements, the waveform (shape) of the coagulation reaction curve or its first derivative curve differs from that of samples from normal subjects without coagulation disorders.The inventors have further found that, based on such waveform differences, samples that may have blood coagulation disorders can be detected from blood samples that do not show a clear prolongation of the clotting time.

[0007] The present invention provides the following as representative embodiments: [1] A method for selecting a blood sample that may have a coagulation abnormality, comprising: 1) obtaining Rs(i), Vs(i), Rmax_s, Vmax_s, VmaxT_s, and Ys(X) for a test blood sample, wherein the test blood sample is a blood sample in which it cannot be determined that APTT is prolonged, i is a measurement point or time, X is a variable and X>0, Rs(i) is the coagulation reaction curve of the test blood sample, Vs(i) is the first differential curve of Rs(i), Rmax_s is the maximum value of Rs(i), Vmax_s is the maximum value of Vs(i), and VmaxT_s is the measurement point or time at which Vs(i) reaches Vmax_s, Ys(X) is the ratio (%) of Rs(i) to Rmax_s at the measurement point or time when Vs(i) reaches X% of Vmax_s, provided that if the measurement point or time when Vs(i) reaches X% of Vmax_s is later than VmaxT_s, Ys(X) is redefined as Ys(200-X); 2) obtaining a parameter Ym(X) for a normal blood sample, where: where i and X are as defined above, j represents the sample number of each sample in the normal blood sample group and is an integer from 1 to k, k represents the total number of samples belonging to the normal blood sample group, and Ym j (X) is Vm j (i) is Vmax_m j Rm at the measurement point or time when it reaches X% of j (i) Rmax_m j The ratio (%) of Vm j (i) is Vmax_m j The measurement point or time at which X% of VmaxT_m j If later than Ym j (X) is Ym j (200-X) and Rm j (i) is the coagulation reaction curve of the sample with sample number j in the normal blood sample group, and Vm j (i) is Rm j (i) is the first derivative curve, and Rmax_m j is Rm j (i) is the maximum value of Vmax_m j is Vm j (i) is the maximum value of VmaxT_m j is Vm j (i) is Vmax_m j 3) obtaining an index A for the test blood sample based on the following formula (2), (2)', or (2)": where Fs(X) = Ys(X) and Fm(X) = Ym(X) or Fs(X) = Ys(X) - Ys(c), and Fm(X) = Ym(X) - Ym(c) or Fs(X) = Ys(X) / Ys(c), and Fm(X) = Ym(X) / Ym(c), a>0, and a≦b, 0<c≦M, and M is the maximum value of X; 4) In the above formula (2), (2)' or (2)", Ys(X) and Ys(c) are respectively set to Ym(X) and Ym(X). j (X) and Ym j(c) replacing (a) with (b) and (c) obtaining an index A for each sample in the normal blood sample group; and 5) comparing the index A for the test blood sample with a statistical value of index A for each sample in the normal blood sample group. [2] The method of [1], wherein (5) includes calculating SDI_A, which represents a standard deviation index of index A for the test blood sample, according to the following formula: SDI_A = |([index A for the test blood sample] - [average value of index A for each sample in the normal blood sample group]) / [standard deviation of index A for each sample in the normal blood sample group]|. [3] The method of [2], further comprising selecting the test blood sample as a blood sample that may have a coagulation abnormality if SDI_A is at or above a predetermined threshold. [4] The method of [2], further comprising: obtaining APTTs for the test blood sample and each sample in the normal blood sample group; calculating SDI_APTT, which represents a standard deviation index of APTTs for the test blood sample, according to the following formula: SDI_APTT = |([APTT for the test blood sample] - [mean APTT for each sample in the normal blood sample group]) / [standard deviation of APTT for each sample in the normal blood sample group]|; and calculating rSDI_A, which represents a ratio of SDI_A to SDI_APTT, according to the following formula: rSDI_A = (SDI_A) / (SDI_APTT). [5] The method of [4], further comprising selecting the test blood sample as a blood sample that may have a coagulation abnormality if SDI_A and rSDI_A are at or above a predetermined threshold. [6] The method of [4], wherein the standard deviation of APTT for each sample in the normal blood sample group is 2 seconds or more. [7] The method of [3] or [5], further comprising outputting information indicating the result of the selection for the test blood sample. [8] The method of any one of [1] to [7], wherein the blood sample in which it cannot be determined that APTT is prolonged is a sample whose APTT is within a predetermined upper limit of normal + 5 seconds. [9] The method of any one of [1] to [8], wherein the blood sample is plasma.

[10] The method of any one of [1] to [9], wherein the coagulation abnormality is coagulation factor deficiency or lupus anticoagulant positivity.

[11] The method according to

[10] , wherein the coagulation factor is factor VIII, factor IX, or von Willebrand factor.

[12] Fs(X) = Ys(X) / Ys(c), and

[13] The method according to any one of [1] to

[12] , further comprising: 6) obtaining a parameter Ps(X) based on Rs(i) or Vs(i) for the test blood sample, where i and X are as defined above; 7) obtaining a parameter Pm(X) for a normal blood sample, where PM j (X) is Rm j (i) or Vm j (i) is a parameter based on the above formula (i), where i, j, k, and X are as defined above; 8) obtaining an index S for the test blood sample based on the following formula (5), (5)', or (5)": where Fs(X) = Ps(X) - Ps(c), and Fm(X) = Pm(X) - Pm(c), or Fs(X) = Ps(X) / Ps(c), and Fm(X) = Pm(X) / Pm(c), a>0, and a≦b, 0<c≦M, and M is the maximum value of X; 9) Ps(X) and Ps(c) in the above formula (5), (5)' or (5)" are respectively set to Pm j (X) and Pm j (c) to obtain an index S for each sample in the normal blood sample group; and (10) comparing the index S for the test blood sample with the statistical value of the index S for each sample in the normal sample group.

[14] Ps(X) represents the measurement point or time at which Rs(i) reaches X% of its coagulation reaction end point, and Pm j (X) is Rm j The method according to

[13] , wherein (i) represents the measurement point or time at which Vs(i) reaches X% of its coagulation reaction end point value, a = 3 to 97, b = 3 to 97, c = 3 to 97, 0 < X ​​≦ 100.

[15] Ps(X) represents the measurement point or time at which Vs(i) reaches X% of its maximum value, provided that if Ps(X) is greater than Ps(100), Ps(X) is redefined as Ps(200 - X), and Pmj (X) is Vm j represents the measurement point or time at which (i) reaches X% of its maximum value, where Pm j (X) is Pm j If it is greater than (100), Pm j (X) is Pm j (200-X), where a = 3 to 98, b = 102 to 197, and c = 3 to 197.

[16] Ps(X) represents the minimum value of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to

[13] , wherein (i) represents the minimum value of the measurement point or time at which Vs(i) reaches X% of its maximum value, a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​≦ 100.

[17] Ps(X) represents the maximum value of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to

[13] , wherein (i) represents the maximum value of the measurement point or time at which Vs(i) reaches X% of its maximum value, a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​≦ 100.

[18] Ps(X) represents the midpoint between the minimum and maximum values ​​of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to

[13] , wherein (i) represents the midpoint between the minimum and maximum values ​​of the measurement point or time at which Vs(i) reaches X% of its maximum value, and a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​≦ 100.

[19] Ps(X) represents the length between the minimum and maximum values ​​of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to

[13] , wherein (i) represents the length between the minimum and maximum values ​​of the measurement points or times at which the signal reaches X% of its maximum value, and a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​< 100.

[20] Ps(X) represents the weighted average time of Vs(i), and Pm j (X) is Vm j (i) represents a weighted average time, which is calculated according to the following formula (4): In the formula, V(i) is Vs(i) or Vm j (i), t1 and t2 respectively represent the minimum and maximum values ​​of the measurement point or time at which V(i) reaches X% of its maximum value, provided that when V(i) is less than X% of the maximum value, V(i) is considered to be 0, a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​≦ 100.

[21] The method according to

[13] , wherein Ps(c) represents the measurement point or time at which Vs(i) reaches c% of its maximum value, PM j (c) is Vm j The method according to any one of

[13] to

[20] , wherein (i) represents the measurement point or time at which the index S reaches c% of its maximum value.

[22] The method according to any one of

[13] to

[21] , wherein 10) includes calculating SDI_S, which represents the standard deviation index of the index S for the test blood sample, according to the following formula: SDI_S = |([index S for the test blood sample] - [mean value of index S for each sample in a normal blood sample group]) / [standard deviation of index S for each sample in a normal blood sample group]|.

[23] The method according to

[22] , further comprising selecting the test blood sample as a blood sample that may have a coagulation abnormality if: SDI_A is at or above a predetermined threshold, or SDI_A and rSDI_A are at or above a predetermined threshold; and SDI_S is at or above a predetermined threshold.

[24] The method of

[22] , further comprising calculating rSDI_S, which represents the ratio of SDI_S to SDI_APTT, according to the following formula: rSDI = SDI_S / SDI_APTT.

[25] The method of

[24] , further comprising selecting the test blood sample as a blood sample that may have a coagulation abnormality, if: SDI_A is at or above a predetermined threshold, or SDI_A and rSDI_A are at or above a predetermined threshold; and SDI_S and rSDI_S are at or above a predetermined threshold.

[26] The method of

[23] or

[25] , further comprising outputting information indicating the result of the selection for the test blood sample.

[0008] According to the method of the present invention, blood samples that may have a coagulation disorder can be detected from blood samples that do not show a clear prolongation of APTT. The present invention makes it possible to detect blood samples from subjects who may have a blood coagulation disorder that could not be detected by conventional APTT screening tests. Furthermore, the present invention makes it possible to confirm whether a sample with an APTT outside the reference range truly has a coagulation disorder (whether it is a pseudo-disorder).

[0009] Explanation of Ys(X). A and B: Rs(i) and Vs(i), and Ys(X) of a test specimen with a coagulation disorder. The distortion of the Ys(X) curve is indicated by an arrow. C and D: Rm of a normal specimen. j (i) and Vm j (i), and Ym j (X). E:Ys(X) and Ym j (X) overlay. The solid line is Ys(X) and the dashed line is Ym j(X) is shown. An embodiment of the process of the method for selecting a specimen that may have a coagulation disorder according to the present invention. An embodiment of the process of the method for selecting a blood specimen that may have a coagulation disorder according to the present invention, including a step of selecting a test specimen based on APTT. Differences in coagulation reactions between FVIII-deficient specimens and other specimen types. A to C: coagulation reaction curves, D to F: first derivative curves. U on the vertical axis represents turbidity units (TU). NL, NM, and NH represent specimens whose APTTs are close to the lower, middle, and upper limits of the normal range, respectively, for the NP group. FVIII represents Abn specimens (FVIII). Differences in coagulation reactions between FIX-deficient specimens and other specimen types. The descriptions of A to F and specimen types are the same as in Figure 5. FIX represents Abn specimens (FIX). Differences in coagulation reactions between VW specimens and other specimen types. The descriptions of A to F and specimen types are the same as in Figure 5. VW represents Abn specimens (VW). Differences in coagulation reactions between LA-positive specimens and other specimen types. The descriptions of A to F and sample types are the same as in Figure 5. LA indicates Abn samples (LA). This figure explains the indicator A-1 used in Example 1-1. NL and NH indicate samples in which the APTT of the NP group is close to the lower and upper limits of the normal range, respectively. FVIII, FIX, VW, and LA indicate Abn samples. NA indicates the average value of the NP group. NL-NA and NH-NA indicate the differences between the NL and NH values ​​and the NA value, respectively. FVIII-NA, FIX-NA, VW-NA, and LA-NA indicate the differences between the Abn samples (FVIII, FIX, VW, and LA) and the NA value. A, B: A-1 for each sample. C: SDI_APTT (gray bar), SDI_A based on A-1 (black bar), and rSDI_A (white bar) for each sample. The legends for the black bars in Figures A, B, and C show a and b used in formula (2a) to calculate the index A-1 in the format [a:b]. N1 to N12 indicate samples from the NP group, F8, F9, VW, and LA indicate samples from the Abn group, F8 indicates FVIII, and F9 indicates FIX. c1 to c5 indicate samples from the Cont group. NP_max (+) indicates the maximum value of A-1 in the NP group. * in Figures A and B indicates samples where A-1 is greater than the threshold. * in Figure C indicates that both SDI_A and rSDI_A exceed the threshold. Figure explaining the index A-2 used in Example 1-2. The description of the samples is the same as in Figure 9. A: A-2 for each sample.B: SDI_APTT (gray bar), SDI_A (black bar) and rSDI_A (white bar) for each sample. In the legends of the black bars in Figures A and B, a, b, and c used in formula (2b) to calculate index A-2 are expressed in the format [a:b] / [c]. The figure legend is the same as Figure 10. A diagram explaining index A-3 used in Example 1-3. The sample legend is the same as Figure 9. A: A-3 for each sample. B: SDI_APTT (gray bar), SDI_A (black bar) and rSDI_A (white bar) for each sample. In the legends of the black bars in Figures A and B, a, b, and c used in formula (2c) to calculate index A-3 are expressed in the format [a:b] / [c]. The figure legend is the same as Figure 10. Changes in SDI_A for A-1 depending on the calculation conditions. The maximum SDI_A (NP_Max; ×) among NP group samples and the SDI_A (●) among Abn samples are shown for each SDI_A calculation condition. The horizontal scale of the figure represents a and b used in the calculation formula for index A as "a:b." A: FVIII sample, B: FIX sample, C: VW sample, D: LA sample. Calculation conditions for SDI_A for A-1 in FVIII. Cases where the SDI_A of Abn samples exceeded the maximum SDI_A among NP group samples are indicated by hatching. Calculation conditions for SDI_A for A-1 in FIX. The same as in Figure 15-2. Calculation conditions for SDI_A for A-1 in VW. The same as in Figure 15-2. Calculation conditions for SDI_A for A-1 in LA. The same as in Figure 15-2. Changes in SDI_A for A-2 depending on calculation conditions. The legend for this figure is the same as for Figure 15-1. Calculation conditions for SDI_A for A-2 in FVIII. The legend for this figure is the same as for Figure 15-2. Calculation conditions for SDI_A for A-2 in FIX. The legend for this figure is the same as for Figure 15-2. Calculation conditions for SDI_A for A-2 in VW. The legend for this figure is the same as for Figure 15-2. Calculation conditions for SDI_A for A-2 in LA. The legend for this figure is the same as for Figure 15-2. Changes in SDI_A for A-3 depending on the calculation conditions. The legend for this figure is the same as for Figure 15-1. Calculation conditions for SDI_A for A-3 in FVIII. The legend for this figure is the same as for Figure 15-2. Calculation conditions for SDI_A for A-3 in FIX. The legend for this figure is the same as for Figure 15-2. Calculation conditions for SDI_A for A-3 in VW. The legend for this figure is the same as for Figure 15-2.Conditions for calculating SDI_A for A-3 in LA. The legend for the figure is the same as in Figure 15-2. Table 8A shows the average SDI_A for each sample under the condition where rSDI_A > 1. Table 8B shows the average SDI_A for each sample under the condition where rSDI_A > 2. A: SDI_APTT (gray bar), SDI_A based on A-2 (black bar), and rSDI_A (white bar) for each sample used in Example 1-2. The legend for the figure is the same as in Figure 10. B: SDI_APTT (gray bar), SDI_S (black bar), and rSDI_S (white bar) based on S-1 for each sample calculated in Example 3. The legend for the black bar in Figure A shows a, b, and c used in equation (2b) to calculate A-2 in the format [a:b] / [c]. The legend for the black bars in Figure B expresses a, b, and c used in formula (5a) to calculate S-1 in the format [a:b] / [c]. The sample descriptions are the same as in Figure 10. A: S-1 for each sample calculated in Reference Example 1. B, C: SDI_APTT (gray bar), SDI_S (black bar), and rSDI_S (white bar) for indicators S-1 and S-2 for each sample calculated in Reference Example 1. B: Indicator S-1, C: Indicator S-2. The legend for the black bars in Figures A, B, and C expresses a, b, and c used in formulas (5a) and (5b) to calculate indicators S-1 and S-2 in the format [a:b] / [c]. The samples are the same as in Figure 10. * in Figure A indicates samples for which S-1 was greater than the threshold. The * in Figures B and C indicates that both SDI_S and rSDI_S exceed the threshold. SDI_APTT (gray bar), SDI_S (black bar), and rSDI_S (white bar) for each sample calculated in Reference Example 2. A: Indicator S-1, B: Indicator S-2. The legend in the figure is the same as in Figure 19. SDI_APTT (gray bar), SDI_S (black bar), and rSDI_S (white bar) for each sample calculated in Reference Example 3. A: Indicator S-1, B: Indicator S-2. The legend in the figure is the same as in Figure 19. SDI_APTT (gray bar), SDI_S (black bar), and rSDI_S (white bar) for each sample calculated in Reference Example 4. A: Indicator S-1, B: Indicator S-2. The illustration is the same as in FIG.SDI_APTT (gray bar), SDI_S (black bar) and rSDI_S (white bar) for each sample calculated in Reference Example 5. A: Indicator S-1, B: Indicator S-2. The legend in the figure is the same as in Figure 19. SDI_APTT (gray bar), SDI_S (black bar) and rSDI_S (white bar) for each sample calculated in Reference Example 6. A: Indicator S-1, B: Indicator S-2. The legend in the figure is the same as in Figure 19. SDI_APTT (gray bar), SDI_S (black bar) and rSDI_S (white bar) for each sample calculated in Reference Example 7. A: Indicator S-1, B: Indicator S-2. The legend in the figure is the same as in Figure 19.

[0010] All patents, non-patent documents, and other publications cited herein are hereby incorporated by reference in their entirety.

[0011] In the measurement of activated partial thromboplastin time (APTT) in blood coagulation tests, a predetermined reagent is added to a test blood sample, the subsequent blood coagulation reaction is measured, and the coagulation time (APTT) is calculated from the coagulation reaction data. Blood coagulation reactions are measured using common means, such as optical means for measuring scattered light intensity, transmittance, absorbance, etc., or mechanical means for measuring plasma viscosity. Blood coagulation reactions are generally represented by a coagulation reaction curve, which shows the change in the amount of coagulation reaction over time. In this specification, blood samples, blood coagulation reactions, and blood coagulation times may be simply referred to as samples, coagulation reactions, and coagulation times, respectively. Furthermore, in this specification, blood coagulation abnormalities may be simply referred to as coagulation abnormalities, and blood samples with coagulation abnormalities may be referred to as abnormal samples.

[0012] In APTT measurements, samples with APTTs within a predetermined reference range are typically considered normal (no suspicion of coagulation abnormalities), while samples with APTTs exceeding the reference range are suspected of coagulation abnormalities. However, the sensitivity of APTT to each coagulation abnormality factor, such as coagulation factors, heparin, or coagulation factor inhibitors, can vary depending on the reagents and analytical equipment used. Such differences in sensitivity can result in overlooking patients with coagulation abnormalities. It has also been reported that samples with APTTs within the reference range may contain samples from patients with mild hemophilia. Patients with such coagulation abnormalities are at risk of unexpected bleeding during surgery, even if their APTTs are within the reference range. Overlooking patients with mild hemophilia or coagulation abnormalities who do not demonstrate a significant APTT prolongation in preoperative testing is a significant clinical problem. Meanwhile, in the field of clinical testing, the reference range for APTT is generally set as a range within 95% of the statistical distribution of APTTs in a healthy population without disease, excluding 2.5% on either side. This means that 5% of healthy individuals without coagulation disorders will have an APTT outside the reference range ("pseudo-abnormality"). Until now, no established method has been known for determining whether a specimen with an APTT outside the reference range has a coagulation disorder (pseudo-abnormality).

[0013] The present inventors have discovered that blood samples from patients with coagulation disorders exhibit waveforms of their coagulation reaction curves or their first derivative curves that differ from those of samples from normal subjects (normal sample group), even when the APTT does not show a clear prolongation. In other words, samples whose waveforms of their coagulation reaction curves or their first derivative curves differ from those of normal sample group may have coagulation disorders.

[0014] The present invention provides a method for selecting a blood sample that may have a coagulation abnormality. In the present invention, a blood sample in which it is not certain that APTT prolongation is present is used as a test sample. In the present invention, a parameter reflecting the waveform of the coagulation reaction data of the test sample obtained by APTT measurement and a parameter reflecting the waveform of the coagulation reaction data of a normal sample are determined, and the presence or absence of a coagulation abnormality in the test sample is detected based on the difference between these parameters. The present invention makes it possible to detect abnormal samples that do not show clear APTT prolongation and tend to be overlooked by conventional APTT measurements. Furthermore, the present invention can provide information for evaluating whether a sample suspected of having a coagulation abnormality based on APTT truly has a coagulation abnormality (whether it is a false abnormality).

[0015] The method of the present invention will now be described.

[0016] 1. Test Samples Test samples in the methods of the present invention are samples for which the presence or absence of coagulation abnormalities has not been determined by conventional APTT measurements. Typically, such test samples do not show clear prolongation of the APTT and the presence of APTT prolongation cannot be confirmed, such as samples with APTTs within the normal range or slightly prolonged from the normal range. A more specific example of such a test sample is a sample with an APTT within the upper limit of normal + 5 seconds. The lower limit of the APTT of the test sample is not particularly limited, but from the perspective of improving detection efficiency by targeting more suspicious samples, it is desirable to set it at the lower limit of normal. Preferably, samples that show an APTT within the above range (preferably between the lower limit of normal and the upper limit of normal + 5 seconds) in conventional coagulation tests can be selected as test samples for the methods of the present invention, assuming that there is no clear prolongation of the APTT. On the other hand, samples with clearly prolonged APTTs, such as those with an APTT exceeding the upper limit of normal + 5 seconds, are determined to be samples with coagulation abnormalities and therefore do not necessarily need to be subjected to the methods of the present invention.

[0017] The "normal range" of APTT in this specification is synonymous with the term "reference range" in the field of clinical testing, as described above. The APTT of a sample can be calculated according to the usual APTT measurement procedure described below. Since the APTT is affected by the reagents and analytical equipment used in the measurement, the normal range of APTT used in the method of the present invention can be predetermined by those skilled in the art depending on the reagents and analytical equipment used in the APTT measurement.

[0018] In the method of the present invention, the test sample is preferably plasma from a subject collected for a coagulation test. An anticoagulant commonly used in coagulation tests may be added to the sample. For example, plasma can be obtained by collecting blood using a blood collection tube containing sodium citrate and then centrifuging the blood.

[0019] 2. Acquisition of Clotting Reaction Data 2.1. Clotting Reaction Measurement Clotting reaction data for a sample can be acquired according to the usual procedure for clotting reaction measurement in APTT measurement. Specifically, in clotting reaction measurement, an APTT measurement reagent is added to a sample to initiate a blood clotting reaction. The clotting reaction in a mixture containing the reagent and the sample is measured. APTT measurement reagents are commercially available (e.g., APTT Reagent Coagpia APTT-N and Coagpia APTT-N Calcium Chloride Solution; both manufactured by Sekisui Medical Co., Ltd.). Coagulation reaction measurement can be performed using conventional means, such as optical means for measuring scattered light intensity, transmittance, absorbance, etc., or mechanical means for measuring plasma viscosity. In the following description, the method of the present invention will be described using clotting reaction measurement based on scattered light intensity as an example.

[0020] The start of the clotting reaction is typically defined as the time when the sample is mixed with the reagent to initiate the clotting reaction, but other timings may also be defined as the start of the reaction. The duration of the clotting reaction measurement may be, for example, several tens of seconds to approximately seven minutes from the time when the sample and reagent are mixed. This measurement time may be an arbitrarily determined fixed value, or it may be continued until the end of the clotting reaction of each sample is detected. During this measurement time, measurement of the progress of the clotting reaction (measurement of the amount of scattered light) may be repeated at predetermined intervals. For example, measurements may be performed at 0.1-second intervals. The temperature of the mixed solution during the measurement is kept under normal conditions, for example, 30°C or higher and 40°C or lower, preferably 35°C or higher and 39°C or lower. Furthermore, various measurement conditions may be appropriately set depending on the test sample, reagent, measurement means, etc.

[0021] The series of operations in the coagulation reaction measurement described above can be performed using an automatic analyzer. An example of an automatic analyzer is the CP3000 automatic blood coagulation analyzer (manufactured by Sekisui Medical Co., Ltd.). Alternatively, some of the operations may be performed manually. For example, sample preparation may be performed manually, and subsequent operations may be performed by the automatic analyzer.

[0022] 2.2. Acquisition of a Coagulation Reaction Curve A coagulation reaction curve R(i) of a sample is acquired from the measured coagulation reaction data. Here, "i" is a variable representing the number of measurement points or the time (also referred to simply as the number of measurement points and time, respectively) from the start of the coagulation reaction. For example, if the measurement (photometric) interval is 0.1 seconds, time is expressed as 0.1 × the number of measurement points. That is, R(i) may be a function of the number of measurement points or a function of time. Generally, the coagulation reaction curve R(i) is obtained by performing noise removal or smoothing processing on the measurement values ​​of the coagulation reaction measurement using conventional means. Alternatively, R(i) may be obtained by zero-point adjustment or relative value conversion of the measurement data D(i) that has been subjected to the noise removal or smoothing processing. The zero-point adjusted R(i) may be, for example, a curve obtained by shifting D(i) so that its initial value is 0. The relative valued R(i) can be calculated, for example, according to the formula: R(i) = [(D(i) - Dmin) / (Dmax - Dmin)] × f (where D(i) represents R(i) before relative valued, Dmax and Dmin represent the maximum and minimum values ​​of D(i), respectively, and f is an arbitrary constant that corresponds to the maximum value of the relative valued R(i)).

[0023] 2.3. Detection of the Clotting Reaction End Point Re The clotting reaction end point Re in R(i) can be detected as needed. Re is R(i) at the point where R(i) reaches a plateau; R(i) at the point where the first derivative curve of R(i) reaches a peak and then decreases to 0 or a constant value (see WO2021 / 206107); R(i) at the earliest point where the integrated ratio of R(i) in a short time period is less than a threshold value (e.g., 1.001) (WO2021 / 132552), etc. It can be determined according to any criteria. Re detection may be performed after acquiring R(i) up to a predetermined measurement time, or Re detection may be performed in parallel with the acquisition of R(i), and acquisition of R(i) may be terminated once Re is detected. In the latter case, it is possible to shorten the measurement time for one sample to the minimum necessary. For example, the procedures described in WO2021 / 206107 or WO2021 / 132552 allow the detection of Re to be carried out in parallel with the acquisition of R(i) (so-called real-time detection of Re).

[0024] As one embodiment of the method of the present invention, an example of a detection procedure for Re based on the method described in WO 2021 / 132552 will be described in detail. The integrated ratio of R(i) during a short time period is defined as Z(i) and is calculated using the following formula: Integrated ratio Z(i) = Rb(i) / Ra(i) Ra(i) = sum of R(i-m) to R(i-1) Rb(i) = sum of R(i+1) to R(i+m) In the above formula, i represents the measurement point number, and m can be set appropriately depending on the measurement conditions and analysis items of the coagulation reaction, for example, m = 10 to 30. R(i) at the earliest measurement point or time point at which Z(i) is less than the threshold Zs is detected as the coagulation reaction end point Re. Zs can be set appropriately depending on the analysis item. For example, in the case of APTT measurement, Zs is preferably 1.050 or less, more preferably in the range of 1.010 to 1.001. In order to prevent erroneous detection of Re due to an abnormal initial reaction, it is preferable to calculate Z(i) after i reaches a predetermined calculation start point and R(i) becomes equal to or greater than a predetermined value. In this procedure, while measuring the coagulation reaction, R(i) is acquired and Z(i) is calculated in parallel, and Re can be detected.

[0025] 2.4. Obtaining a First-Order Derivative Curve A first-order derivative curve (clotting reaction rate curve) V(i) is obtained from the coagulation reaction curve R(i). Differentiation of the coagulation reaction curve can be performed by any method, for example, by calculating the average slope within a section. Alternatively, V(i) may be converted into a relative value. The relative value V(i) can be calculated, for example, according to the formula: V(i) = [(D(i) - Dmin) / (Dmax - Dmin)] × f (where D(i) represents V(i) before relative value conversion, Dmax and Dmin represent the maximum and minimum values ​​of D(i), respectively, and f is an arbitrary constant corresponding to the maximum value of the relative value V(i)).

[0026] In this specification, R(i) includes the coagulation reaction curve with or without the relativization, unless otherwise specified. Also, in this specification, V(i) includes the first derivative curve with or without the relativization, unless otherwise specified.

[0027] 3. APTT Calculation The clotting time (APTT) of a sample can be calculated from the clotting reaction data of the sample obtained by the clotting reaction measurement. The method for calculating the APTT is not particularly limited. For example, the APTT can be calculated by any method based on R(i) or V(i). Examples of the APTT calculation method include, but are not limited to, a method in which the point at which R(i) reaches N% of the end point of the clotting reaction (for example, the above-mentioned Re) is calculated as the clotting time (percentage detection method); a method in which the point at which V(i) reaches N% of its maximum value is calculated as the clotting time; and a method in which the point at which the integrated ratio of R(i) in a short time period reaches a predetermined value is set as the calculation starting point Te, and the point at which R(i) reaches N% of R(Te) is calculated as the clotting time (see Japanese Patent Laid-Open No. 6-249855). Examples include a method of calculating the clotting time based on the time-dependent change in the cumulative ratio of R(i) over a short time period (see WO2021 / 132552); a method of calculating the clotting time based on the weighted average time of V(i) (see WO2021 / 177452); and a method of calculating the clotting time from the point Te when V(i) reaches a predetermined value after reaching its maximum value, when R(i) reaches N% of R(Te) (see WO2021 / 206107).

[0028] Based on the calculated APTT of the sample, a test sample to which the method of the present invention is applied can be selected. In one embodiment, the coagulation reaction of an arbitrary sample is measured, the APTT is calculated, and then a sample in which it cannot be determined that the APTT is prolonged is selected as a test sample of the present invention. In another embodiment, a sample in which it is known from existing coagulation reaction data that the APTT is not clearly prolonged is selected as a test sample of the present invention.

[0029] 4. Obtaining Index A 4.1. Obtaining Parameter Ys(X) In the method of the present invention, parameter Ys(X) is obtained based on the waveform of the coagulation reaction curve of the test sample and its first derivative curve. From parameter Ys(X) for the test sample and the corresponding parameter Ym(X) for a normal sample, index A is obtained for assessing the possibility that the test sample has a coagulation abnormality.

[0030] The parameter Ys(X) will be specifically described. In the following specification, the coagulation reaction curve of a test sample and its first derivative curve will be referred to as Rs(i) and Vs(i), respectively. Rmax_s, Vmax_s, VmaxT_s, and Ys(X) can be calculated from Rs(i) and Vs(i). Here, Rmax_s is the maximum value of Rs(i), which may be the coagulation reaction end point (hereinafter also referred to as Re_s) of Rs(i) described above. Vmax_s is the maximum value of Vs(i), and VmaxT_s is the measurement point or time at which Vs(i) reaches Vmax_s.

[0031] Ys(X) represents the ratio (%) of Rs(VxT_s) (i.e., Rs(i) at VxT_s) to Rmax_s, where VxT_s is the measurement point or time at which Vs(i) reaches X% of Vmax_s. X is a variable, and 0<X≦100. X can vary from its initial value in increments α (α is preferably an integer from 1 to 5). In one example, X is a variable that varies in increments of 1 within the range of 1<X≦100 (i.e., X={1, 2, 3, ..., 97, 98, 99, 100}). In another example, X is a variable that varies in increments of 5 within the range of 3 to 98 (i.e., X={3, 8, 13, ..., 93, 98}). Alternatively, Ys(X) may be expressed as the average value from Ys(X−K) to Ys(X+K). In this case, K is preferably smaller than the increment α of X described above. For example, if K=2, Ys(X) can be expressed as the average value of Ys(8) to Ys(12) when X=10, or as the average value of Ys(13) to Ys(17) when X=15. Therefore, a series of Ys(X) corresponding to the varying X as described above can be obtained.

[0032] However, because the first derivative curve is a mountain-shaped curve, there are multiple VxT_s (measurement points or times at which Vs(i) reaches X% of Vmax_s), and they can exist before or after Vmax_s. Therefore, if VxT_s is after VmaxT_s, Ys(X) is redefined as Ys(200-X). Therefore, the final range of X for Ys(X) is 0<X<200. The obtained parameter Ys(X) is used to calculate index A.

[0033] Ys(X) will be explained using FIG. 1. FIG. 1 shows Rs(i) and Vs(i) (each representing a relative value with the maximum value set to 100%). The black circles on Vs(i) represent points where Vs(i) is X% of Vmax_s (X is 3 to 93 in increments of 10, and 100). Because Vs(i) is a mountain-shaped curve, points where Vs(i) reaches X% of Vmax_s exist before and after Vmax_s. The black triangles on Rs(i) indicate Rs(i) at the measurement points or times where Vs(i) reaches X% of Vmax_s (X = 43 and 100). Since Rs(i) in the figure is represented as a relative value with the maximum value (Rmax_s) set to 100%, these represent Ys(X). Of these, the second black triangle from the left is Rs(i) at Vmax_s (X=100), i.e., Ys(100). The subsequent black triangles are points after VmaxT_s, and are therefore redefined as Ys(200-X). As a specific example, the first black triangle from the left represents Ys(43), which is Rs(i) at the point in time before VmaxT_s when Vs(i) is 43% of Vmax_s, and the third black triangle from the left represents Ys(157), which is Rs(i) at the point in time after VmaxT_s when Vs(i) is 43% of Vmax_s.

[0034] In the method of the present invention, the corresponding parameter Ym(X) for the normal specimen is obtained. Specifically, the parameter Ym is calculated based on the coagulation reaction curve and the first derivative curve of each specimen in the normal specimen group. j (X) are obtained, and their average value is taken as Ym(X). Each normal sample in the normal sample group can be a sample known to be free of coagulation abnormalities. The total number of normal samples used is preferably 5 or more, more preferably 10 to 30.

[0035] In this specification, the coagulation reaction curve and its first derivative curve of each sample in the normal sample group are respectively referred to as Rm j (i) and Vm jHere, j represents the specimen number of each specimen belonging to the normal specimen group and is an integer between 1 and k, and k represents the total number of specimens belonging to the normal specimen group. Therefore, the coagulation reaction curves Rm1(i), Rm2(i), ... Rm for each of the k normal specimens are k (i) is obtained. Alternatively, the first derivative curves Vm1(i), Vm2(i), ... Vm for each of the k normal samples are obtained. k (i) is obtained. For each sample in the normal sample group, Rm j (X) and Vm j (X) to Rmax_m j , Vmax_m j , VmaxT_m j , and Ym j (X) can be calculated (j=1 to k). Here, Rmax_m j is Rm j (i), which is the maximum value of Rm j (i) The end point of the coagulation reaction (hereinafter referred to as Re_m j Vmax_m j is Vm j (i) is the maximum value of VmaxT_m j is Vm j (i) is Vmax_m j is the measurement point or time at which

[0036] Ym j (X) is Vm j (i) is Vmax_m j The measurement point or time at which X% of VxT_m is reached j When Rm j (V x T_m j ) (i.e., VxT_m j In Rm j (i)) Rmax_m j X is a variable, and 0<X≦100. In the same manner as in the calculation procedure for Ys(X) described above, X is varied, and a series of Ym corresponding to the varied X is calculated. j (X) can be obtained. However, as in the case of Ys(X) described above, VxT_m j is VmaxT_m j If later than Ymj (X) is Ym j (200-X). Therefore, Ym j The final range of X for (X) is 0<X<200.

[0037] Next, Ym j The average value Ym(X) of (X) is obtained. Ym(X) is expressed by the following formula (1), where X is as described above. The obtained Ym(X) is used to calculate the index A.

[0038] Figures 2A and 2B show Rs(i) and Vs(i) of a test specimen with a coagulation disorder and the Ys(X) obtained from them. Figures 2C and 2D show Rm of a normal specimen. j (i) and Vm j (i), and Ym obtained therefrom j The Vs(i) of the test specimen has a shoulder after the maximum peak, and therefore the curve of Ys(X) has a distortion (indicated by an arrow in FIG. 2B) just after X is 100. On the other hand, the Ym of the normal specimen j (X) is a smooth curve that rises to the right after X reaches 100. Figure 2E shows the relationship between Ys(X) and Ym j Ys(X) (solid line) from the test sample and Ym (X) from the normal sample are overlaid. j (X) (dashed line) shows a difference in shape.

[0039] 4.2. Obtaining index A Next, the index A for the test sample is obtained from the obtained Ys(X) and Ym(X). The index A is calculated according to the following formula (2). Here, Fs(X) = Ys(X) and Fm(X) = Ym(X) or Fs(X) = Ys(X) - Ys(c), and Fm(X) = Ym(X) - Ym(c) or Fs(X) = Ys(X) / Ys(c), and Fm(X) = Ym(X) / Ym(c), a > 0 and a ≦ b, c is a constant and 0 < c ≦ M, where M is the maximum value of X. Therefore, in the present invention, in the calculation procedure of Ys(X) and Ym(X) described above, X is varied to include the range from a to b, and a series of Ys(X) and Ym(X) are obtained. If necessary, Ys(c) and Ym(c), which are predetermined values ​​representing the values ​​of Ys(X) and Ym(X) when X = c, are obtained. The index A can be obtained using the series of Fs(X) and Fm(X) obtained from the obtained series of Ys(X) and Ym(X) and, if necessary, Ys(c) and Ym(c).

[0040] Note that Fm(X) is j It can also be expressed by the following formula based on (X), which will be understood to be equivalent to [Ym(X) / Ym(c)].

[0041] In formula (2), the values ​​of a, b, and c can be set appropriately. In one embodiment, a is preferably 3 to 197, more preferably 3 to 53 or 100 to 197, and b is preferably 3 to 197, more preferably 3 to 73 or 100 to 197. c is preferably 23 to 197, more preferably 98 to 197.

[0042] The index A is the sum of squares of Fs(X) (however, when a = b in the above formula (2), it is the square of Fs(X)). Furthermore, it can be understood that the index A can be expressed by the following formula (2)' or formula (2)" instead of the above formula (2). For convenience in the following formulas, the index expressed by formula (2)' will be represented as A', and the index expressed by formula (2)" will be represented as A", but in this specification, the indexes expressed by formula (2), formula (2)', and formula (2)" may all be referred to as A. a, b, and c in formula (2)' and formula (2)" may be set in the same way as in formula (2).

[0043] The above-mentioned formula (2) for calculating index A can be divided into the following formulas (2a), (2b), and (2c) depending on the types of Fs(X) and Fm(X). Therefore, in this specification, the value calculated by formula (2a) is referred to as index A-1, the value calculated by formula (2b) as index A-2, and the value calculated by formula (2c) as index A-3. The values ​​of a and b in formula (2a) and the values ​​of a, b, and c in formulas (2b) and (2c) can be set appropriately depending on the types of Ys(X) (and Ym(X)) within the same range as in formula (2).

[0044] Similar to the index A described above, index A-1 can be expressed by the following formula (2a)' or formula (2a)" instead of the above formula (2a), index A-2 can be expressed by the following formula (2b)' or formula (2b)" instead of the above formula (2b), and index A-3 can be expressed by the following formula (2c)' or formula (2c)" instead of the above formula (2c). For convenience, in the following formulas, the index represented by formula (2a)' is referred to as A'-1, the index represented by formula (2a)" is referred to as A"-1, the index represented by formula (2b)' is referred to as A'-2, An index represented by formula (2b)" is represented as A"-2, an index represented by formula (2c)' is represented as A'-3, and an index represented by formula (2c)" is represented as A"-3. However, in this specification, an index represented by formula (2a), formula (2a)', and formula (2a)" may all be referred to as A-1, or an index represented by formula (2b), formula (2b)', and formula (2b)" may all be referred to as A-2, or an index represented by formula (2c), formula (2c)', and formula (2c)" may all be referred to as A-3. a and b in formula (2a)' and formula (2a)" may be set in the same way as in formula (2a), a, b, and c in formula (2b)' and formula (2b)" may be set in the same way as in formula (2b), and a, b, and c in formula (2c)' and formula (2c)" may be set in the same way as in formula (2c).

[0045] In the above procedure for calculating index A, Ym(X) and Fm(X) can be calculated in advance according to the types of Ys(X) and Fs(X) obtained from the test sample. In a specific example, prior to measuring coagulation reaction data from the test sample, Ym(X) is calculated from the coagulation reaction data of each sample in an existing normal sample group, and Fm(X) is calculated using this data according to formula (2). Depending on the types of Ys(X) and Fs(X) obtained from the test sample, index A for the test sample is calculated according to formula (2) using Fm(X) obtained from the corresponding Ym(X).

[0046] 5. Obtaining Index S 5.1. Obtaining Parameter Ps(X) In the method of the present invention, in addition to the aforementioned index A, an index S can be further obtained. Index S, together with index A, can be used to evaluate the possibility that a test sample has a coagulation abnormality.

[0047] To calculate the index S, a parameter Ps(X) for the test sample based on Rs(i) or Vs(i) and a corresponding parameter Pm(X) for the normal sample are obtained. X is a variable and X>0. Pm(X) is expressed by the following equation (3): j (X) is the average value.

[0048] PM j The normal sample group used to calculate (X) may be a sample group different from the normal sample group used to calculate Ym(X) above, but is preferably the same sample group. Therefore, the total number of normal samples contained in the normal sample group is preferably 5 or more, more preferably 10 to 30.

[0049] Ps(X), Pm j Specific examples of (X) include those described in (a) to (g) below.

[0050] (a) Ps(X) represents the measurement point or time at which Rs(i) reaches X% of its coagulation reaction end point. Pm j (X) is the coagulation reaction curve Rm for each sample in the normal sample group. j(i) represents the measurement point or time when X% of the coagulation reaction end point is reached. That is, Ps(X) and Pm j (X) satisfies the following formula: Rs(Ps(X))=Re_s×X% Rm j (P.M. j (X)) = Re_m j × X% where, as described above, Re_s represents the end point of the coagulation reaction of Rs(i), and Re_m j is Rm j (i) represents the end point of the coagulation reaction, and 0<X≦100.

[0051] (b) Ps(X) represents the measurement point or time at which Vs(i) reaches X% of its maximum value (i.e., the same as VxT_s described above). j (X) is the Vm for each sample in the normal sample group. j The measurement point or time when (i) reaches X% of its maximum value (i.e., the aforementioned VxT_m j That is, Ps(X) and Pm j (X) satisfies the following formula: Vs(Ps(X))=Vmax_s×X% Vm j (P.M. j (X))=Vmax_m j × X% In the above formula, as described above, Vmax_s represents the maximum value of Vs(i), and Vmax_m j is Vm j (i), and 0<X≦100. Since the first derivative curve is a mountain-shaped curve, Ps(X) and Pm j There are multiple (X) and they can exist before or after Ps(100) (the point where Vmax_s is reached). Therefore, if the above Ps(X) is larger than Ps(100), Ps(X) is redefined as Ps(200-X). Similarly, Pm j (X) is Pm j If it is greater than (100), Pm j (X) is Pm j Therefore, Ps(X) and Pm j In (X) and Pm(X), the range of X is finally 0<X<200.

[0052] (c) Ps(X) represents the minimum value of the measurement point or time at which Vs(i) reaches X% of its maximum value. j (X) is Vm j (i) represents the minimum value of the measurement point or time at which it reaches X% of its maximum value, where 0<X≦100.

[0053] (d) Ps(X) represents the maximum value of the measurement point or time at which Vs(i) reaches X% of its maximum value. j (X) is Vm j (i) represents the maximum value of the measurement point or time at which it reaches X% of its maximum value, where 0<X≦100.

[0054] (e) Ps(X) represents the midpoint between the minimum and maximum values ​​(calculated in (c) and (d) above) of the measurement point or time when Vs(i) reaches X% of its maximum value. Pm j (X) is Vm j (i) represents the midpoint between the minimum and maximum values ​​of the measurement point or time at which it reaches X% of its maximum value, where 0<X≦100.

[0055] (f) Ps(X) represents the length between the minimum and maximum values ​​(calculated in (c) and (d) above) of the measurement point or time when Vs(i) reaches X% of its maximum value. Pm j (X) is Vm j (i) represents the length between the minimum and maximum values ​​of the measurement point or time at which it reaches X% of its maximum value, where 0<X<100.

[0056] (g) Ps(X) represents the weighted average time of Vs(i). Pm j (X) is Vm j (i) represents the weighted average time. The weighted average time is calculated according to the following formula (4). In the formula, V(i) is Vs(i) or Vm j (i), t1 and t2 respectively represent the minimum and maximum values ​​of the measurement points or times at which V(i) reaches X% of its maximum value, and 0<X≦100, provided that when V(i) is less than X% of the maximum value, V(i) is considered to be 0.

[0057] Ps(X) and Pm according to (a) to (g) above jIn the calculation procedure of (X), X is Ys(X) and Ym j As in the calculation of (X), Ps(X) can be varied with a given initial value and increment α, or Ps(X) can be expressed as the average value from Ps(X−K) to Ps(X+K), and Pm j (X) can be expressed similarly. Ps(X) and Pm j The initial value of X and the increment α for calculating (X) are the above-mentioned Ys(X) and Ym j (X) may be the same as or different from the calculation of (X). Thus, a series of Ps(X) and Pm(X) depending on the varying X can be obtained.

[0058] 5.2. Obtaining the index S Next, the index S for the test sample is obtained from the obtained Ps(X) and Pm(X). The index S is calculated according to the following formula (5). Here, Fs(X) = Ps(X) - Ps(c), and Fm(X) = Pm(X) - Pm(c), or Fs(X) = Ps(X) / Ps(c), and Fm(X) = Pm(X) / Pm(c), a > 0, and a ≦ b, c is a constant and 0 < c ≦ M, where M is the maximum value of X. Therefore, in the present invention, in the calculation procedure of Ps(X) and Pm(X) described above, X is varied so as to fall within the range from a to b and include c, and a series of Ps(X) and Pm(X) is obtained. The index S can be obtained using the obtained series of Ps(X) and Pm(X), and the series of Fs(X) and Fm(X) obtained from Ps(c) and Pm(c).

[0059] Note that Fm(X) is Pm j It can also be expressed by the following formula based on (X), which will be understood to be equivalent to [Pm(X) / Pm(c)].

[0060] The index S is the sum of squares of Fs(X) (however, when a = b in the above formula (5), it is the square of Fs(X)). Furthermore, it can be understood that the index S can be expressed by the following formula (5)' or formula (5)" instead of the above formula (5). For convenience in the following formulas, the index expressed by formula (5)' will be represented as S', and the index expressed by formula (5)" will be represented as S", but in this specification, the indexes expressed by formula (5), formula (5)', and formula (5)" may all be referred to as S. a, b, and c in formula (5)' and formula (5)" may be set in the same way as in formula (5).

[0061] Fs(X) represents the difference or ratio of Ps(X) obtained in 5.1 above to Ps(c). Similarly, Fm(X) represents the difference or ratio of Pm(X) to Pm(c). Ps(c) and Pm(c) may be predetermined values ​​representing the values ​​of Ps(X) and Pm(X), respectively, when X = c.

[0062] Alternatively, for Ps(c) and Pm(c), other predetermined values ​​can be used instead of the predetermined values ​​representing the values ​​of Ps(X) and Pm(X) when X = c described above. For example, if Ps(X) and Pm(X) comply with any of (a), (c) to (g) in 5.1 above, Ps(c) and Pm(c) calculated in accordance with (b) in 5.1 above can be used instead of Ps(c) and Pm(c) calculated in accordance with each of (a), (c) to (g). In this case, Ps(c) is the measurement point or time at which Vs(i) reaches c% of its maximum value, and Pm(c) is as follows: Here, P j (c) is Vm j (i) represents the measurement point or time at which c% of the maximum value is reached.

[0063] The above-mentioned formula (5) for calculating the index S can be divided into the following formulas (5a) and (5b) depending on the types of Fs(X) and Fm(X). Therefore, in this specification, the value calculated by formula (5a) is referred to as index S-1, and the value calculated by formula (5b) is referred to as index S-2.

[0064] Similar to the index S described above, index S-1 can be expressed by the following formula (5a)' or formula (5a)" instead of the formula (5a), and index S-2 can be expressed by the following formula (5b)' or formula (5b)" instead of the formula (5b). For convenience, in the following formulas, the index represented by formula (5a)' will be represented as S'-1, the index represented by formula (5a)" as S"-1, the index represented by formula (5b)' as S'-2, and the index represented by formula (5b)" as S"-2. However, in this specification, the indexes represented by formula (5a), formula (5a)', and formula (5a)" may all be referred to as S-1, or the indexes represented by formula (5b), formula (5b)', and formula (5b)" may all be referred to as S-2. In formula (5a)′ and formula (5a)″, a, b, and c may be set in the same manner as in formula (5a), and in formula (5b)′ and formula (5b)″, a, b, and c may be set in the same manner as in formula (5b).

[0065] In the formulas (5), (5a) and (5b), the values ​​of a, b and c can be set appropriately depending on the type of Ps(X) (and Pm(X)).

[0066] In one embodiment, when Ps(X) and Pm(X) comply with (a) of 5.1. above, in formula (5), a is preferably 3 to 97, b is preferably 3 to 97, and c is preferably 3 to 97, provided that when Ps(c) and Pm(c) comply with (b) of 5.1. above, c is preferably 98 to 102. More specifically, when Ps(c) and Pm(c) comply with (b) of 5.1. above, in formula (5a), a is preferably 3 to 97, more preferably 3 to 77, b is preferably 3 to 97, more preferably 23 to 97, and c is preferably 98 to 102, more preferably 99 to 101. When Ps(c) and Pm(c) comply with (b) of 5.1. above, in formula (5b), a is preferably 3 to 97, more preferably 3 to 77, b is preferably 3 to 97, more preferably 23 to 97, and c is preferably 98 to 102, more preferably 99 to 101. In the case of (b) above, a is preferably 3 to 87, more preferably 3 to 85, b is preferably 4 to 97, more preferably 23 to 97, and c is preferably 98 to 102, more preferably 99 to 101.

[0067] In one embodiment, when Ps(X) and Pm(X) comply with (b) of 5.1. above, in formula (5), a is preferably 3 to 98, b is preferably 102 to 197, and c is preferably 3 to 197. More specifically, in formula (5a), a is preferably 3 to 98, more preferably 3 to 93, b is preferably 102 to 197, more preferably 123 to 197, and c is preferably 3 to 197, more preferably 98 to 100. In formula (5b), a is preferably 3 to 98, more preferably 3 to 93, b is preferably 102 to 197, more preferably 123 to 197, and c is preferably 3 to 197, more preferably 3 to 117. In formulas (5), (5a), and (5b), c may or may not be within the range of a to b.

[0068] In one embodiment, when Ps(X) and Pm(X) comply with (c) of 5.1. above, in formula (5), a is preferably 3 to 98, b is preferably 3 to 98, and c is preferably 3 to 197. More specifically, in formula (5a), a is preferably 3 to 98, more preferably 23 to 53, b is preferably 3 to 98, more preferably 53 to 98, and c is preferably 3 to 197, more preferably 13 to 68. In formula (5b), a is preferably 3 to 98, more preferably 3 to 93, b is preferably 3 to 98, more preferably 3 to 83, and c is preferably 13 to 192, more preferably 48 to 172. In formulas (5), (5a), and (5b), c may or may not be within the range of a to b.

[0069] In one embodiment, when Ps(X) and Pm(X) comply with (d) of 5.1. above, in formula (5), a is preferably 3 to 98, b is preferably 3 to 98, and c is preferably 3 to 197. More specifically, in formula (5a), a is preferably 3 to 98, more preferably 3 to 53, b is preferably 13 to 98, more preferably 23 to 83, and c is preferably 3 to 197, more preferably 100 to 157. In formula (5b), a is preferably 3 to 98, more preferably 3 to 53, b is preferably 3 to 98, more preferably 23 to 93, and c is preferably 3 to 197, more preferably 3 to 73. In formulas (5), (5a), and (5b), c may or may not be within the range of a to b.

[0070] In one embodiment, when Ps(X) and Pm(X) comply with (e) of 5.1. above, in formula (5), a is preferably 3 to 98, b is preferably 3 to 98, and c is preferably 3 to 197. More specifically, in formula (5a), a is preferably 3 to 98, more preferably 3 to 83, b is preferably 3 to 98, more preferably 13 to 98, and c is preferably 3 to 197, more preferably 100 to 107. In formula (5b), a is preferably 3 to 98, more preferably 13 to 93, b is preferably 3 to 98, more preferably 33 to 98, and c is preferably 3 to 197, more preferably 3 to 127. In formulas (5), (5a), and (5b), c may or may not be within the range of a to b.

[0071] In one embodiment, when Ps(X) and Pm(X) comply with (f) of 5.1. above, in formula (5), a is preferably 3 to 98, b is preferably 3 to 98, and c is preferably 3 to 197. More specifically, in formula (5a), a is preferably 3 to 98, more preferably 23 to 98, b is preferably 3 to 98, more preferably 13 to 98, and c is preferably 3 to 98, more preferably 23 to 98. In formula (5b), a is preferably 3 to 83, more preferably 13 to 83, b is preferably 3 to 98, more preferably 33 to 98, and c is preferably 3 to 197, more preferably 13 to 88 and 132 to 197. In formulas (5), (5a), and (5b), c may or may not be within the range of a to b.

[0072] In one embodiment, when Ps(X) and Pm(X) comply with (g) of 5.1. above, in formula (5), a is preferably 3 to 98, b is preferably 3 to 98, and c is preferably 3 to 197. More specifically, in formula (5a), a is preferably 3 to 98, more preferably 3 to 83, b is preferably 3 to 98, more preferably 43 to 73, and c is preferably 3 to 197, more preferably 100 to 107. In formula (5b), a is preferably 3 to 98, more preferably 3 to 93, b is preferably 3 to 98, more preferably 13 to 98, and c is preferably 3 to 197, more preferably 3 to 127. In formulas (5), (5a), and (5b), c may or may not be within the range of a to b.

[0073] In the above procedure for calculating the index S, Pm(X) and Fm(X) can be calculated in advance according to the types of Ps(X) and Fs(X) obtained from the test sample. In a specific example, prior to measuring coagulation reaction data from the test sample, Pm(X) according to (a) to (g) in 5.1. above is calculated from the coagulation reaction data of each sample in an existing normal sample group, and Fm(X) according to formulas (5a) and (5b) is calculated using this. Depending on the types of Ps(X) and Fs(X) obtained from the test sample, the index S for the test sample is calculated according to formula (5a) or (5b) using Fm(X) calculated from the corresponding Pm(X).

[0074] 6. Selection of a blood sample that may have a coagulation abnormality The aforementioned index A and index S for the test sample reflect the degree of difference in the waveform of the coagulation reaction curve or its first derivative curve between the test sample and a normal sample. The larger index A or index S indicates that the waveform of the coagulation reaction curve of the test sample is more different from the waveform of the curve of the normal sample. Therefore, index A or index S can be used to evaluate whether the test sample is likely to have a coagulation abnormality. Indicator A and index S can each be used alone as an index for evaluating the possibility that the test sample has a coagulation abnormality, but index A and index S can also be used in combination. In the method of the present invention, at least index A is used to evaluate whether the test sample is likely to have a coagulation abnormality.

[0075] Considering that test samples evaluated as possibly having a coagulation abnormality by the method of the present invention do not have a clear prolongation of the APTT, they are likely to be samples from patients who have some kind of coagulation abnormality but do not show clear symptoms, such as mild hemophilia. Therefore, the method of the present invention makes it possible to select samples from patients with coagulation abnormalities that have previously been difficult to detect. Furthermore, test samples determined to have a possible coagulation abnormality can be subjected to other tests, as necessary, to determine the presence or absence and type of coagulation abnormality. Furthermore, test samples determined to have an APTT prolonged beyond the upper limit of the normal range but not to have a possible coagulation abnormality can be inferred to have a prolonged APTT due to a false APTT abnormality.

[0076] Coagulation disorders include clotting factor deficiencies and lupus anticoagulant (LA) positivity, including factor VIII (FVIII), factor IX (FIX), and von Willebrand factor (VWF).

[0077] 6.1. Evaluation Based on Index A In one embodiment of the present invention, the test sample is evaluated for the possibility of having a coagulation abnormality by comparing the index A of the test sample with the statistical value of index A of a group of normal samples. In a preferred embodiment, index A is calculated for each sample in an arbitrary normal sample group, and the maximum value of these is compared with index A of the test sample. If index A of the test sample is greater than the maximum value of the normal sample group, the test sample is likely to have a coagulation abnormality.

[0078] In a preferred embodiment of the present invention, the standard deviation index (SDI) of index A for the test sample is calculated to compare index A of the test sample with the statistical value of index A of the normal sample group. More specifically, the absolute value of the SDI of index A for the test sample is calculated, which is also referred to herein as SDI_A, and is calculated as follows: SDI_A = |([index A for the test sample] - [average value of index A for each sample in the normal sample group]) / [standard deviation of index A for each sample in the normal blood sample group] | The normal sample group used in the above formula can be samples known to be free of coagulation abnormalities. It may be a sample group different from the normal sample group used in the calculation of Ym(X) above, but is preferably the same sample group. The total number of normal samples included in the normal sample group is preferably 5 or more, more preferably 10 to 30. Preferably, the standard deviation of APTT for the normal sample group is 2 seconds or more. Index A for each sample in the normal sample group is calculated by replacing the test sample with each sample in the normal sample group, using the same method as in 4. For example, if SDI_A is based on index A-1 according to formula (2a), index A-1 for normal samples can also be calculated using formula (2a).

[0079] Based on the calculated SDI_A of the test sample, it is possible to evaluate whether the test sample is likely to have a coagulation abnormality. More specifically, a test sample whose SDI_A is at or above a threshold value is likely to have a coagulation abnormality. The threshold value can be set as appropriate, for example, by calculating the SDI_A for each sample in an arbitrary normal sample population and setting a value greater than the maximum value of these as the threshold value. In a preferred embodiment, the threshold value is preferably 3 or greater, more preferably 4 or greater.

[0080] 6.2. Evaluation Based on Indicators A and S In another embodiment of the present invention, Indicators A and S of a test sample are compared with the statistical values ​​of Indicators A and S of a group of normal samples, respectively, to evaluate whether the test sample is likely to have a coagulation abnormality. In a preferred embodiment, if the test sample is likely to have a coagulation abnormality based on Indicator A as described above and satisfies the criteria for Indicator S as described below, the test sample is likely to have a coagulation abnormality.

[0081] In a preferred embodiment for comparing the index S of a test sample with the statistical value of the index S of a group of normal samples, the index S is calculated for each sample in an arbitrary normal sample group, and the maximum value of these is compared with the index S of the test sample. Test samples having an index S greater than the maximum value of the normal sample group are considered to meet the criteria for index S.

[0082] In another preferred embodiment, to compare the index S of a test sample with the statistical value of the index S of a group of normal samples, the absolute value of the SDI of the index S for the test sample is calculated, which is also referred to herein as SDI_S, and is calculated as follows: SDI_S = |([index S for the test sample] - [average value of index S for each sample in the normal sample group]) / [standard deviation of index S for each sample in the normal blood sample group]| Test samples having an SDI_S greater than a predetermined threshold are detected as test samples that meet the criteria for index S. The threshold can be set as appropriate; for example, SDI_S can be calculated for each sample in an arbitrary group of normal samples, and a value greater than the maximum value of these can be set as the threshold. In a preferred embodiment, the threshold is preferably 3 or greater, more preferably 4 or greater.

[0083] The SDI_S for the index S-1 or S-2 can be used to evaluate the test sample. For example, a test sample for which either the SDI_S for S-1 or the SDI_S for S-2 is equal to or greater than a threshold value is detected as a test sample that meets the criteria for index S. Alternatively, the SDI_S for each of the indexes S-1 and S-2 can be determined and used to evaluate the test sample. For example, a test sample for which both the SDI_S for S-1 and the SDI_S for S-2 are equal to or greater than a threshold value is detected as a test sample that meets the criteria for index S.

[0084] The normal sample group used to calculate SDI_S above can be samples known to be free of coagulation abnormalities, and may be a different sample group from the normal sample group used to calculate SDI_A above, but is preferably the same sample group. The index S for each sample in the normal sample group can be calculated using the same procedure as for the index S for the test sample, in accordance with Section 5. above, but replacing the test sample with each sample in the normal sample group. For example, if SDI_S is based on index S-1 according to formula (5a) using Ps(X) according to Section 5.1.(a) above, index S-1 for normal samples can also be calculated using Section 5.1.(a) and formula (5a).

[0085] 6.3. Evaluation Taking APTT into Account Furthermore, in the present invention, the SDI of the APTT for the test sample is used, if necessary, to select samples that may have a coagulation abnormality. More specifically, the absolute value of the SDI of the APTT for the test sample is calculated, which is also referred to herein as SDI_APTT, and is calculated as follows: SDI_APTT = |([APTT for the test sample] - [mean APTT for each sample in the normal sample group]) / [standard deviation of APTT for each sample in the normal blood sample group] | The normal sample group used in the above formula is the same sample group used to calculate SDI_A. More preferably, the same normal sample group is used to calculate SDI_A, SDI_S, and SDI_APTT. The APTT, mean value, and standard deviation for each sample in the normal sample group can be calculated in advance, for example, prior to measuring coagulation reaction data from the test sample. Next, the ratio of SDI_A or SDI_S to SDI_APTT (hereinafter also referred to as rSDI_A and rSDI_S, respectively) is calculated as follows: rSDI_A=SDI_A / SDI_APTT rSDI_S=SDI_S / SDI_APTT

[0086] The SDI_A and rSDI_A can be used to evaluate the likelihood that a test specimen has a coagulation disorder. In one embodiment, a test specimen for which SDI_A and rSDI_A are both at or above a threshold is evaluated as possibly having a coagulation disorder. Alternatively, the rSDI_A or rSDI_S can be used together with SDI_A and SDI_S to evaluate the likelihood that a test specimen has a coagulation disorder. In one embodiment, a test specimen for which SDI_A, SDI_S, and rSDI_A are all at or above a threshold is evaluated as possibly having a coagulation disorder. In another embodiment, a test specimen for which SDI_A, SDI_S, rSDI_A, and rSDI_S are all at or above a threshold is evaluated as possibly having a coagulation disorder. The thresholds for SDI_A and SDI_S are as described above. The threshold values ​​of rSDI_A and rSDI_S can be set appropriately, but the threshold value of rSDI_A is preferably 1 or more, more preferably 2 or more, and the threshold value of rSDI_S is preferably 1 or more, more preferably 2 or more. Regarding SDI_S and rSDI_S, SDI_S and rSDI_S for either S-1 or S-2 may be used, but SDI_S and rSDI_S for both S-1 and S-2 may also be used.

[0087] The index A or index S, APTT, and their average value and standard deviation for each sample in the normal sample group can be calculated in advance. For example, prior to measuring coagulation reaction data from the test sample, index A can be calculated from the existing coagulation reaction data of each sample in the normal sample group according to 4. above, or indexes S-1 and S-2 can be calculated according to 5. above using each of (a) to (g) in 5.1. above. When calculating SDI_S, an appropriate index S corresponding to index S for the test sample is used.

[0088] 6.4. Output of Results The selection results obtained above can be output in any format. For example, information regarding whether the test sample is likely to have a coagulation abnormality (in other words, whether the waveform of the test sample's coagulation reaction curve or its first derivative curve differs from that of a normal sample) can be output in any format. When the waveform differs from that of a normal sample, a more detailed output example can be a flag indicating information such as "waveform differs from normal sample," "additional testing necessary," or "possible coagulation abnormality." Along with the selection result information, the APTT of the test sample and information regarding whether APTT prolongation is present can also be output. For example, if the APTT of the test sample is prolonged beyond the upper limit of the normal range, the APTT and a flag indicating APTT prolongation can be output. On the other hand, if the APTT of the test sample is within the upper limit of the normal range, the APTT can also be output. Alternatively, information regarding the APTT can be output even if the test sample is not selected as having a possible coagulation abnormality and therefore information regarding the selection result is not output.

[0089] 7. Application to Other Clotting Reaction Measurement Methods The method of the present invention has been described above using the example of clotting reaction measurement based on the amount of scattered light. However, a person skilled in the art would be able to apply other clotting reaction measurement methods (e.g., clotting reaction measurement based on transmittance, absorbance, viscosity, etc.) to the clotting reaction measurement of the present invention, and such applications are therefore within the scope of the present invention.

[0090] 8. Program and Apparatus The series of processes of the method of the present invention described above can be performed automatically by an automatic analysis device. For example, an automatic analysis device controlled by a computer program can be used. Therefore, one aspect of the present invention is a program for performing the method of the present invention described above. Another aspect of the present invention is an apparatus for performing the method of the present invention described above. The execution of the method of the present invention by the apparatus can be controlled by the program of the present invention. A further aspect of the present invention is a system for performing the method of the present invention, which system includes the apparatus or program for performing the method of the present invention described above.

[0091] An embodiment of the apparatus of the present invention will be described below. In this embodiment of the apparatus of the present invention, an automatic analyzer 1 is an automatic analyzer 1 including a control unit 10, an operation unit 20, a measurement unit 30, and an output unit 40. The configuration of the automatic analyzer 1 will be described below.

[0092] The control unit 10 controls the overall operation of the automated analyzer 1. The control unit 10 may be configured by a computer (e.g., a personal computer). The control unit 10 includes a CPU, memory, storage, a communication interface (I / F), and can process commands from the operation unit 20, control the operation of the measurement unit 30, store and analyze measurement data received from the measurement unit 30, store analysis results, and control the output of analysis results by the output unit 40. The control unit 10 may also be connected to other devices such as external media or a host computer. In the control unit 10, the computer that controls the operation of the measurement unit 30 and the computer that analyzes the data measured by the measurement unit 30 may be the same or different.

[0093] The operation unit 20 acquires input from an operator and transmits the acquired input information to the control unit 10. For example, the operation unit 20 includes a user interface (UI) such as a keyboard or a touch panel. Under the control of the control unit 10, the output unit 40 outputs the detection results of samples that may have coagulation abnormalities, and, as necessary, the coagulation reaction data of the samples measured by the measurement unit 30, and the results of R(i), V(i), APTT, etc. based on the data. For example, the output unit 40 includes a display device such as a display.

[0094] The measuring unit 30 executes a series of processes for a blood coagulation test and acquires measurement data of the coagulation reaction of a sample including a blood sample. The measuring unit 30 includes various equipment and analysis modules necessary for a blood coagulation test, such as a sample container for storing the blood sample, a reagent container for storing the test reagent, a reaction container for the reaction between the sample and the reagent, a probe for dispensing the blood sample and the reagent into the reaction container, a light source, a detector for detecting scattered light or transmitted light from the sample in the reaction container, a data processing circuit for sending data from the detector to the control unit 10, and a control circuit for controlling the processing of the measuring unit 30 in response to commands from the control unit 10. Alternatively, the measuring unit 30 is not necessary when calculating R(i), V(i), APTT, etc. using already acquired coagulation reaction data.

[0095] The control unit 10 analyzes the coagulation reaction of the sample based on the coagulation reaction data. This analysis may include calculation of R(i) and V(i), calculation of APTT, calculation of Ys(X), Ps(X), index A or index S, and detection of a sample that may have a coagulation abnormality using index A. The R(i) and V(i) data may be generated by the control unit 10 based on measurement data from the measurement unit 30, or may be generated by another device, for example, the measurement unit 30, and sent to the control unit 10. The control unit 10 also includes a memory for storing the APTT, Ym(X), and index S for normal samples. j (X), Ym(X), Pm j (X), Pm(X), and indicators A and S, or threshold values ​​used for detecting a specimen that may have a coagulation abnormality, etc. may be stored in the control unit 10. Alternatively, the control unit 10 may retrieve these values ​​stored in an external device or on a network for the detection.

[0096] The above analysis can be performed by a program for carrying out the method of the present invention. Thus, the control unit 10 can be provided with a program for the method of the present invention for selecting a blood sample that may have a blood coagulation disorder.

[0097] The analysis results from the control unit 10 are sent to the output unit 40 and output. The output may take any form, such as display on a screen, transmission to a host computer, or printing. The output information from the output unit may include the APTT of the test sample, information on the possibility of the test sample having a coagulation abnormality, etc. The type of information output from the output unit may be controlled by the program of the present invention.

[0098] 9. Analysis Flow One embodiment of the process of the method for selecting a blood sample that may have a coagulation abnormality according to the present invention when index A is used, which is carried out under the control of the program of the present invention, is described below and in Figure 3. S1: Acquire coagulation reaction data (Rs(i) and Vs(i)) of the test sample. S2: Calculate APTT based on Rs(i) or Vs(i). S3: Calculate Ys(X) based on Rs(i) and Vs(i). S4: Calculate index A using Ys(X). S5: Compare index A with a threshold. If index A exceeds the threshold, it is determined that there is a "possible coagulation abnormality." S6: Output APTT and the determination result.

[0099] Another embodiment of the process of the method for selecting a blood sample that may have a coagulation disorder according to the present invention, which is carried out under the control of the program of the present invention, is described below and in FIG. 4 . This process includes a step of selecting a test sample based on APTT. The threshold conditions used in this process are an example in which the SDI and SDI ratio (SDI_A and rSDI_A) for index A are used. S01: Acquire coagulation reaction data (Rs(i) and Vs(i)) of the test sample. S02: Calculate APTT based on Rs(i) or Vs(i). S03: Determine whether the APTT of the test sample exceeds a predetermined value (UL+5 (seconds); UL = upper limit of normal range). APTT≦UL+5 →Go to S04 APTT>UL+5 →Go to S10 S04: Calculate Ys(X). S05: Calculate index A from Ys(X). S06: Calculate SDI_A and rSDI_A. S07: Compare SDI_A and rSDI_A with the threshold value. If both SDI_A and rSDI_A exceed the threshold value → go to S08 If neither SDI_A nor rSDI_A exceeds the threshold value → go to S09 S08: Determine whether the APTT of the test sample exceeds the UL. APTT>UL → go to S40 APTT≦UL → go to S50 S09: Determine whether the APTT of the test sample exceeds the UL. APTT>UL → go to S20 APTT≦UL → go to S30 S10: Output the APTT together with a flag indicating "APTT>UL+5". S20: Output the APTT together with a flag indicating "APTT>UL". S30: Output the APTT. S40: Output the APTT, a flag indicating "APTT>UL", and a flag indicating "possible coagulation abnormality". S50: Output APTT and a flag indicating "possible coagulation abnormality."

[0100] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. The coagulation reaction measurements in the following examples were carried out according to the procedure for APTT measurement.

[0101] 1. Methods 1.1) Samples Normal sample (NP): Plasma from healthy individuals without coagulation disorders (N1-N12, total n = 12). Abnormal sample (Abn): Plasma from patients with coagulation disorders (total n = 4). FVIII deficiency (FVIII) (n = 1). FIX deficiency (FIX) (n = 1). von Willebrand disease (VW) (n = 1). LA positive (LA) (n = 1). Control sample (Cont) (total n = 5). APTT series samples (c1-c5) were prepared as follows using Control P-N I, which has a normal APTT, and Control P-N II, which has a prolonged APTT, included with the Coagpia Control P-N (manufactured by Sekisui Medical Co., Ltd.). Control P-N I was used as is for c1. Samples c2-c5 were prepared by mixing Control P-N I and Control P-N II at different ratios to achieve different APTTs.

[0102] 1.2) Coagulation Reaction Measurement: Coagulation reaction measurements of specimens containing specimens were performed using a CP3000 automated blood coagulation analyzer (manufactured by Sekisui Medical Co., Ltd.). 50 μL of specimen was heated in a cuvette at 37°C for 45 seconds, after which 50 μL of APTT measurement reagent at approximately 37°C was added. After a further 171 seconds, 50 μL of calcium chloride solution was added to initiate the coagulation reaction. The reaction was carried out at 37°C. To measure the coagulation reaction, the cuvette was irradiated with light of 660 nm wavelength from an LED light source, and the amount of scattered light at a 90-degree side angle was measured at 0.1-second intervals. The measurement time was 200 seconds.

[0103] 1.3) Obtaining a coagulation reaction curve After smoothing the coagulation reaction measurement data from each sample, including noise removal, a zero-point adjustment process was performed so that the amount of scattered light at the start of measurement was 0. The obtained data was converted into relative values ​​so that the maximum value was 100(%), and a coagulation reaction curve R(i) was created. R(i) was first differentiated and converted into relative values ​​so that the maximum value was 100(%) to calculate V(i). The maximum value Vmax of V(i) for each sample and the time VmaxT at that time were calculated.

[0104] 1.4) Detection of Rmax (clotting reaction end point Re) The R(i) at the earliest time point at which the integrated ratio Z(i) of the coagulation reaction curve R(i) (see WO2021 / 132552) becomes less than the integrated ratio threshold Zs was detected as the coagulation reaction end point Re. The integrated ratio threshold Zs was set to 1.001. The integrated ratio Z(i) at time point i was calculated as follows: Integrated ratio Z(i) = Pb(i) / Pa(i) Pa(i) = Sum of P(i-20) to P(i-1) Pb(i) = Sum of P(i+1) to P(i+20) The calculated Re was taken as the maximum value Rmax of R(i).

[0105] 1.5) Calculation of APTT The time point when R(i) reached 50% of Re was determined as the APTT. The APTT for each sample was as follows: NP: 26.1 to 39.4 seconds. Abn: 34.3 to 41.2 seconds (FVIII: 41.2 seconds, FIX: 35.7 seconds, VW: 38.7 seconds, LA: 34.3 seconds). Cont: 26.4 to 28.6 seconds. Since the upper limit of the normal range for APTT under the measurement conditions of this example was 39 seconds, the APTTs for the Abn and Cont groups were within the upper limit of the normal range + 5 seconds (44 seconds).

[0106] 1.6) Calculation of Index A The parameter Ys(X) was calculated for each specimen in the NP group, Abn group, and Cont group. Ys(X) was calculated as the ratio (%) of Rs(i) to Rmax of each specimen at the time when V(i) of each specimen reaches X% of its Vmax (X is a variable, 0<X≦100). However, if the time when V(i) reaches X% of its Vmax is later than VmaxT, Ys(X) was redefined as Ys(200-X). Furthermore, the parameter Ym j (X) (j = 1 to 12), and then average them to obtain Ym(X). As a result, Ys(X) and Ym(X) (X varied from 3 to 197 in increments of 10 and 100) were obtained.

[0107] Using the obtained Ys(X) and Ym(X), the index A (A-1, A-2, and A-3) for each sample was calculated according to the following formulas (2a) to (2c). The calculation formula for index A and a, b, and c in the formula are as shown in Table 1 below.

[0108]

[0109] 1.7) Calculation of the index S For each specimen in the NP group, Abn group, and Cont group, Ps(X) was calculated according to (a) to (g) in the above section 5.1. ("Obtaining the parameter Ps(X)"). Furthermore, the parameter of each specimen in the NP group was calculated as Pm j (X) (j = 1 to 12), and then averaged to obtain Pm(X).

[0110] The indicators S-1 and S-2 for each sample were calculated according to the following formulas (5a) and (5b).

[0111] The parameters Ps(X), Pm(X), and the calculation formula used to calculate S-1 and S-2, as well as a, b, and c in the formula, are as shown in Table 2 below. However, the following correction was made to Ps(X) and Pm(X) in accordance with 5.1.(b): if Ps(X) is greater than Ps(100), Ps(X) is redefined as Ps(200-X); and Pm j (X) is Pm j If it is greater than (100), Pm j (X) to Pm j Redefined as (200-X).

[0112]

[0113] 1.8) Calculation of SDI For each sample in the Abn group, the SDI (SDI_A, SDI_S, and SDI_APTT) was calculated for index A (A-1 to A-3), index S (S-1 and S-2), and APTT as follows. SDI_A = | ([Index A for each sample in the Abn group] - [Average value of Index A for each sample in the NP group]) / [Standard deviation of Index A for each sample in the NP group] | SDI_S = | ([Index S for each sample in the Abn group] - [Average value of Index S for each sample in the NP group]) / [Standard deviation of Index S for each sample in the NP group] | SDI_APTT = | ([APTT for each sample in the Abn group] - [Average value of APTT for each sample in the NP group]) / [Standard deviation of APTT for each sample in the NP group] | The SDI ratios (rSDI_A and rSDI_S) were calculated as follows: rSDI_A = SDI_A / SDI_APTT rSDI_S = SDI_S / SDI_APTT

[0114] 1.9) Criteria for detecting coagulation abnormalities (i) Samples with index A greater than a threshold were determined to have coagulation abnormalities. The detection threshold was set at 1.2 to 1.5 times the maximum index A value in the NP group. (ii) Samples with both SDI_A and rSDI_A greater than their thresholds were determined to have coagulation abnormalities. The detection thresholds were set at 4 for SDI_A and 2 for rSDI_A.

[0115] 2. Coagulation Reaction 2.1) FVIII Deficiency Figure 5 shows the coagulation reaction of FVIII-deficient samples (FVIII) in the Abn group. Figures 5A-C show the coagulation reaction curves, and Figures 5D-F show the first-derivative curves. In the figures, NL, NM, and NH indicate samples in the NP group with APTTs near the lower, middle, and upper limits of the normal range, respectively, while FVIII indicates Abn samples (FVIII). Figures 5A and 5D show the measured coagulation reaction U (turbidity unit of scattered light, TU) and its first-derivative. In Figures 5B and 5E, the reactions are relative values ​​so that the maximum reaction value in Figures 5A and 5D corresponds to 100%. In Figure 5C, the reaction time is relative so that the time point at which the reaction is 50% in Figure 5B corresponds to 100% (time) on the horizontal axis. In Figure 5F, the reaction time is relative so that the time point at which the reaction is 100% in Figure 5E corresponds to 100% (time) on the horizontal axis. As shown in Figure 5D and E, the first-order derivative curves for FVIII showed an asymmetric peak, with a shoulder appearing after the peak top. When comparing FVIII with NM, differences were observed after the peak top of the first-order derivative curves, as shown in Figure 5F.

[0116] 2.2) FIX Deficiency Figure 6 shows the clotting response of the FIX-deficient specimen (FIX) from the Abn group. The data shown in Figures 6A-F are the same as those in Figures 5A-F, except that the Abn specimen was FIX. As shown in Figure 6F, the clotting response of FIX differed from that of NM after the peak of the first derivative curve, but the difference was smaller than that of FVIII.

[0117] 2.3) von Willebrand (VW) Figure 7 shows the clotting response of the Abn group VW specimen (VW). The data shown in Figures 7A-F are the same as those in Figures 5A-F, except that the Abn specimen is VW. As shown in Figures 7D and 7E, the first-order derivative curve for VW was slightly asymmetric above the peak; that is, the curve descended gradually after the peak top, followed by a rapid decline. Comparing VW with NM, as shown in Figure 7F, a difference was observed in the curve after the peak top, and the difference was slightly larger than that for FVIII.

[0118] 2.4) LA Positive Figure 8 shows the clotting reactions of LA-positive specimens (LA) in the Abn group. The data shown in Figures 8A-F are the same as those in Figures 5A-F, except that the Abn specimens were LA. As shown in Figures 8D and 8E, the first-order derivative curves for LA were slightly asymmetrical above the peak, i.e., the curves showed a gentler rise just before the peak top. Comparing LA with NM, as shown in Figure 8F, differences were observed before the peak top of the first-order derivative curves, and some differences were also observed after the peak top.

[0119] 3. Examples of Coagulation Abnormality Detection Example 1 (1-1) A-1 Figure 9 shows the absolute values ​​of Fs(X), Fs(X) - Fm(X), and Fs(X) - Fm(X) for Abn samples (FVIII, FIX, VW, and LA) for indicator A-1. In the figure, NL and NH indicate samples with APTTs close to the lower and upper limits of the normal range, respectively, for the NP group. FVIII, FIX, VW, and LA indicate Abn samples, and NA indicates the average value for the NP group. The indicator A-1 for Abn samples was greater than that for NL and NH, with X ranging from 43 to 112 for FVIII, 38 to 48, 63 to 68, and 88 to 93 for FIX, 68 to 73, 88 to 93, and 172 to 187 for VW, and 88 to 107 for LA. The range of X, where all A-1s for Abn samples were greater than those for NL and NH, was 88 to 93. Figures 10A and 10B show the A-1s for each sample. The formula for A-1 is shown in Table 1. Figure 10A shows the sum of squares from Fs(93) to Fs(100), while Figure 10B shows the square at Fs(187). Figure 10C shows the SDI_APTT (gray bar), SDI_A (black bar), and rSDI_A (white bar) for A-1 for each sample. N1 to N12 represent samples from the NP group, F8 (FVIII), F9 (FIX), VW, and LA represent samples from the Abn group, and c1 to c5 represent samples from the Cont group. NP_max(+) represents the maximum A-1 value for the NP group, which is the A-1 for NP12 in Figures 10A and 10B. In Figure 10A, A-1 was greater than the threshold (NP_max x 1.5) for FVIII, FIX, and LA, and in Figure 10B, A-1 was greater than the maximum value of the NP group (NP12) x 1.2 for VW. Furthermore, as shown in Figure 10C, the SDI_A and rSDI_A of A-1 were greater than the set thresholds (4 for SDI_A and 2 for rSDI_A) for FVIII, FIX, and LA. This demonstrates that abnormal samples can be detected based on the indicator A-1.

[0120] (1-2) A-2 Figure 11 shows the absolute values ​​of Fs(X), Fs(X) - Fm(X), and Fs(X) - Fm(X) for Abn samples (FVIII, FIX, VW, and LA) for the index A-2. The index A-2 for Abn samples was greater than NL and NH in the ranges of X = 3-38 and 102-197 for FVIII, X = 3-93 and 117-197 for FIX, X = 102-197 for VW, and X = 3-93 and 102-197 for LA. The range of X in which all A-2 values ​​for Abn samples were greater than NL and NH was 117-197. Figure 12A shows the A-2 values ​​for each sample, and Figure 12B shows the SDI_APTT (gray bars), SDI_A (black bars), and rSDI_A (white bars) for A-2 for each sample. The calculation formula for A-2 is shown in Table 1. As shown in Figures 12A and 12B, for all Abn samples (FVIII, FIX, VW, and LA), A-2 was greater than the maximum value of the NP group (NP11) × 1.3, and SDI_A and rSDI_A were greater than the set thresholds. This demonstrates that abnormal samples can be detected based on the indicator A-2.

[0121] (1-3) A-3 Figure 13 shows the absolute values ​​of Fs(X), Fs(X) - Fm(X), and Fs(X) - Fm(X) for Abn samples (FVIII, FIX, VW, and LA) for the index A-3. The index A-3 of the Abn samples was larger than NL and NH in the ranges of X = 23-63 and 102-197 for FVIII, X = 28-58 and 102-197 for FIX, X = 28-43 and 102-172 for VW, and X = 23-93 and 102-197 for LA. The ranges of X in which the A-3 values ​​of all Abn samples were larger than NL and NH were 28-43 and 102-172. Figure 14A shows the A-3 of each sample, and Figure 14B shows the SDI_APTT (gray bar), SDI_A (black bar), and rSDI_A (white bar) for A-3 of each sample. The calculation formula for A-3 is shown in Table 1. As shown in Figures 14A and 14B, for all Abn samples (FVIII, FIX, VW, and LA), A-3 was greater than the maximum value of the NP group (NP11) × 1.3, and SDI_A and rSDI_A were greater than the set thresholds. This demonstrates that abnormal samples can be detected based on the indicator A-3.

[0122] Example 2 (2-1) The index A of normal samples (NP group; N1 to N12) was calculated, and the SDI_A was calculated as follows. The parameters Ys(X), Ym(X), and the calculation formula used in the calculation, as well as a, b, and c in the formula, and the number of calculated SDI_A are as shown in Table 3 below. SDI_A = |([Index A for each sample of the NP group] - [Average value of index A for each sample of the NP group]) / [Standard deviation of index A for each sample of the NP group]|

[0123]

[0124] Table 4 shows the frequency distribution of the maximum SDI_A values ​​for the NP group under each calculation condition. There were calculation conditions under which the SDI_A value exceeded 3, but there were no calculation conditions under which the SDI_A value exceeded 4. For A-2, there were no calculation conditions under which the SDI_A value was 3 or greater. Therefore, it was shown that by setting the threshold for these SDI_A values ​​to 3, test samples with SDI_A values ​​greater than the threshold value can be selected as samples that may have coagulation abnormalities. Furthermore, for A-1 and A-3, there were no samples with SDI_A values ​​greater than 4. Therefore, it was shown that by setting the threshold for these SDI_A values ​​to 4, test samples with SDI_A values ​​greater than the threshold value can be selected as samples that may have coagulation abnormalities.

[0125]

[0126] (2-2) For the Abn samples (FVIII, FIX, VW, and LA) used in Example 1, 229 to 230 SDI_A values ​​shown in Table 3 were calculated for A-1, A-2, or A-3. Figures 15-1A to 15-1D show the maximum SDI_A (x) among the samples in the NP group and the SDI_A (●) of the Abn samples for each SDI_A calculation condition for A-1. The horizontal scale in the figure represents a and b in Equation (2a) used to calculate A-1 as "a:b." Figures 15-2 to 15-5 (Tables 5A to 5D) show the calculation conditions for SDI_A for A-1, and hatching indicates cases where the SDI_A of the Abn samples (FVIII, FIX, VW, and LA) exceeded the maximum SDI_A among the samples in the NP group. The SDI_A of A-1 exceeded the maximum value of the NP group when a≦107 and b≦83 for FVIII, when a≦100 and b=100-107 for FIX, when a=147-187 and b≧177 for VW, and when a and b were 100 or less for LA.

[0127] Figures 16-1A to 16-1D show the maximum SDI_A (x) among the NP group samples and the SDI_A (●) among the Abn samples for each SDI_A calculation condition for A-2. The horizontal scale of the figure represents a and b in formula (2a) used to calculate A-2 as "a:b." Figures 16-2 to 16-5 (Tables 6A to 6D) show the calculation conditions for SDI_A for A-2, and hatching indicates cases where the SDI_A of the Abn samples (FVIII, FIX, VW, LA) exceeded the maximum SDI_A among the NP group samples. The SDI_A of A-2 exceeded the maximum value of the NP group in almost the entire range of a and b for FVIII, in FIX when a was other than 93 to 137, in VW when a was 83 or less and b was 107 to 197, and in the entire range of a and b for LA.

[0128] Figures 17-1A to 17-1D show the maximum SDI_A (x) among the NP group samples and the SDI_A (●) among the Abn samples for each SDI_A calculation condition for A-3. The horizontal scale in the figure represents a and b in formula (2a) used to calculate A-3 as "a:b." Figures 17-2 to 17-5 (Tables 7A to 7D) show the calculation conditions for SDI_A for A-3, and hatching indicates cases where the SDI_A of the Abn samples (FVIII, FIX, VW, LA) exceeded the maximum SDI_A among the NP group samples. The SDI_A of A-3 exceeded the maximum value of the NP group when a was 93 or less and b was 107 to 197, or a was 107 or more, for FVIII, when a was 93 or less and b was 117 to 197, or a was 100 or more, for FIX, when a was 117 or less and b was 107 to 187, for VW, and when a was 23 or less and b was 63 to 197, or a was 33 or more, for LA.

[0129] (2-3) Using the conditions in Table 3, A-1, A-2, and A-3 were calculated for the NP group (N1-N12) and the Abn group (FVIII, FIX, VW, and LA), and the respective SDI_A and rSDI_A were determined. As shown in Figure 17-6, Table 8A shows the average SDI_A values ​​under conditions where rSDI_A > 1 for each sample. Since the maximum value for the NP group was 3.0, values ​​exceeding 3.0 are indicated by hatching and bold text in the table, and "-" indicates that no conditions were met where rSDI_A > 1 was met. Table 8B shows the average SDI_A values ​​under conditions where rSDI_A > 2 for each sample. Values ​​exceeding 3.0 are indicated by hatching and bold text in the table. As shown in Tables 8A and 8B, for A-1, the mean SDI_A values ​​for FVIII and LA were greater than the maximum value for the NP group when rSDI_A > 1, and for FVIII, FIX, and LA when rSDI_A > 2. For A-2 and A-3, the mean SDI_A values ​​for all Abn samples when rSDI_A > 1 were greater than the maximum value for the NP group. Furthermore, the mean SDI_A values ​​when rSDI_A > 2 were equal to or higher than those when rSDI_A > 1, indicating that setting an additional threshold of rSDI_A > 2 enables more accurate detection of abnormal samples. On the other hand, the deviation from the mean of the APTT distribution (SDI_APTT) alone could not distinguish the Abn group from the NP group. It was demonstrated that the Abn group can be distinguished from the NP group by a new perspective, the deviation from the mean of the distribution of index A (SDI_A).

[0130] The results of this example showed that the appropriate threshold value for SDI_A for distinguishing between abnormal and normal samples is 3 or more, or 4 or more. Furthermore, the results of this example show that the calculation conditions for index A used to detect abnormal samples, such as Fs(X) and the conditions a, b, and c used in formula (2), can be optimized depending on the type of abnormal sample to be detected, the desired detection accuracy, and the like. Those skilled in the art will understand that the calculation conditions and number of calculations for index A can be optimized based on the determination results for a large number of normal samples and a large number of abnormal samples with various coagulation abnormality factors.

[0131] As shown in Figures 15-1, 16-1, and 17-1, the pattern of index A (fluctuations in index A due to calculation conditions) may differ depending on the cause of the coagulation abnormality. It can be understood that by creating a database of patterns of index A of abnormal specimens for each cause of coagulation abnormality, and using that database, for example, a machine learning model based on that database, it may be possible to detect specimens that may have various coagulation abnormality causes, or to estimate the coagulation abnormality causes of those specimens.

[0132] Example 3 Figure 18 shows the index A and index S for each sample. Figure 18A shows the SDI_APTT, SDI_A, and rSDI_A for A-2 of each sample shown in Figure 12B. Figure 18B shows the SDI_APTT, SDI_S, and rSDI_S for S-1 of each sample. A-2 and S-1 were calculated for different ranges of X as shown in Tables 1 and 2, respectively, but not only SDI_A and rSDI_A, but also SDI_S and rSDI_S were greater than the set thresholds (4 for SDI_A, 2 for rSDI_A, 4 for SDI_S, and 2 for rSDI_S) for all Abn samples (FVIII, FIX, VW, and LA). In this way, when the same sample is detected as an abnormal sample using both indicator A and indicator S for different ranges of X, it can be interpreted that the accuracy of the detection result is higher than when detection is performed using only one indicator.

[0133] 4. Reference Example Reference Example 1 The parameter Ps(X) was determined according to Section 5.1.(a) above, and used to calculate the indices S-1 and S-2. The formulas for calculating S-1 and S-2 are shown in Table 2. Figure 19A shows the index S-1 for each sample. Figures 19B and 19C show the SDI_APTT, SDI_S, and rSDI_S of the indices S-1 and S-2 for each sample. The legend for the black bars in the figures indicates the values ​​a, b, and c used in formulas (2a) and (2b) used to calculate the indices S-1 and S-2 in the format [a:b] / [c], where [V100] means that Ps(c) was the aforementioned Ps(100). As shown in Figure 19A, the S-1 values ​​for the Abn group (FVIII, FIX, VW, and LA) were all greater than the maximum value (NP12) for the NP group. 19B and 19C, SDI_S and rSDI_S were greater than the set threshold (4 for SDI_S and 2 for rSDI_S) for the Abn group (FVIII, FIX, VW, and LA) for S-1, and for FVIII, FIX, and LA for S-2. This indicates that abnormal samples can be detected based on the indicators S-1 and S-2.

[0134] Reference Example 2: Parameter Ps(X) was determined according to (b) of Section 5.1 above, and used to calculate indicators S-1 and S-2. The calculation formulas for S-1 and S-2 are shown in Table 2. Figures 20A and 20B show the SDI_APTT, SDI_S, and rSDI_S of indicators S-1 and S-2 for each sample. SDI_S and rSDI_S were greater than the set threshold for FVIII, VW, and LA for S-1, and for FVIII and LA for S-2. It was demonstrated that FVIII, VW, and LA samples could be detected based on indicators S-1 or S-2.

[0135] Reference Example 3: Parameter Ps(X) was determined according to (c) of Section 5.1 above, and used to calculate indices S-1 and S-2. The calculation formulas for S-1 and S-2 are shown in Table 2. Figures 21A and 21B show the SDI_APTT, SDI_S, and rSDI_S of indices S-1 and S-2 for each sample. The SDI_S and rSDI_S of indices S-1 and S-2 were greater than the thresholds set for LA. It was demonstrated that LA samples can be detected based on indices S-1 and S-2.

[0136] Reference Example 4: Ps(X) was determined according to (d) of Section 5.1 above, and used to calculate the indicators S-1 and S-2. The calculation formulas for S-1 and S-2 are shown in Table 2. Figures 22A and 22B show the SDI_APTT, SDI_S, and rSDI_S of the indicator S-1 for each sample. The SDI_S and rSDI_S were greater than the set threshold for FVIII and VW for S-1, and for FVIII and LA for S-2. It was demonstrated that FVIII, VW, and LA samples could be detected based on the indicator S-1 or S-2.

[0137] Reference Example 5: Ps(X) was determined according to (e) of Section 5.1 above, and used to calculate the indicators S-1 and S-2. The calculation formulas for S-1 and S-2 are shown in Table 2. Figures 23A and 23B show the SDI_APTT, SDI_S, and rSDI_S of the indicators S-1 and S-2 for each sample. The SDI_S and rSDI_S of the indicators S-1 and S-2 were greater than the thresholds set for the Abn group (FVIII, FIX, VW, and LA). This demonstrated that all abnormal samples could be detected based on the indicators S-1 or S-2.

[0138] Reference Example 6: Ps(X) was determined according to (f) of Section 5.1 above, and used to calculate the indicators S-1 and S-2. The calculation formulas for S-1 and S-2 are shown in Table 2. Figures 24A and 24B show the SDI_APTT, SDI_S, and rSDI_S of the indicators S-1 and S-2 for each sample. SDI_S and rSDI_S were greater than the set threshold for FVIII, VW, and LA for S-1, and for FVIII and LA for S-2. It was demonstrated that FVIII, VW, and LA samples could be detected based on the indicators S-1 or S-2.

[0139] Reference Example 7: Ps(X) was determined according to (g) of Section 5.1 above, and used to calculate the indicators S-1 and S-2. The calculation formulas for S-1 and S-2 are shown in Table 2. Figures 25A and 25B show the SDI_APTT, SDI_S, and rSDI_S of the indicators S-1 and S-2 for each sample. In the Abn group (FVIII, FIX, VW, and LA), the SDI_S and rSDI_S of S-1 and S-2 were greater than the set thresholds. This demonstrated that all abnormal samples could be detected based on the indicators S-1 or S-2.

Claims

1. A method for selecting a blood sample that may have a coagulation abnormality, comprising: 1) obtaining Rs(i), Vs(i), Rmax_s, Vmax_s, VmaxT_s, and Ys(X) for a test blood sample, wherein the test blood sample is a blood sample in which it cannot be determined that APTT is prolonged, i is a measurement point or time, X is a variable and X>0, Rs(i) is the coagulation reaction curve of the test blood sample, Vs(i) is the first derivative curve of Rs(i), Rmax_s is the maximum value of Rs(i), Vmax_s is the maximum value of Vs(i), and VmaxT_s is the measurement point or time at which Vs(i) reaches Vmax_s, Ys(X) is the ratio (%) of Rs(i) to Rmax_s at the measurement point or time when Vs(i) reaches X% of Vmax_s, provided that if the measurement point or time when Vs(i) reaches X% of Vmax_s is later than VmaxT_s, Ys(X) is redefined as Ys(200-X); 2) obtaining a parameter Ym(X) for a normal blood sample, where: where i and X are as defined above, j represents the sample number of each sample in the normal blood sample group and is an integer from 1 to k, k represents the total number of samples belonging to the normal blood sample group, and Ym j (X) is Vm j (i) is Vmax_m j Rm at the measurement point or time when it reaches X% of j (i) Rmax_m j The ratio (%) of Vm j (i) is Vmax_m j The measurement point or time at which X% of VmaxT_m j If later than Ym j (X) is Ym j (200-X) and Rm j (i) is the coagulation reaction curve of the sample with sample number j in the normal blood sample group, and Vm j (i) is Rm j (i) is the first derivative curve, and Rmax_m j is Rm j (i) is the maximum value of Vmax_m j is Vm j (i) is the maximum value of VmaxT_m j is Vm j (i) is Vmax_m j 3) obtaining an index A for the test blood sample based on the following formula (2), (2)', or (2)": where Fs(X) = Ys(X) and Fm(X) = Ym(X) or Fs(X) = Ys(X) - Ys(c), and Fm(X) = Ym(X) - Ym(c) or Fs(X) = Ys(X) / Ys(c), and Fm(X) = Ym(X) / Ym(c), a>0, and a≦b, 0<c≦M, and M is the maximum value of X; 4) In the above formula (2), (2)' or (2)", Ys(X) and Ys(c) are respectively set to Ym(X) and Ym(X). j (X) and Ym j (c) replacing (c) with (d) obtaining an index A for each sample in the normal blood sample group; and (4) comparing the index A for the test blood sample with a statistical value of the index A for each sample in the normal sample group.

2. The method of claim 1, wherein step 5) includes calculating SDI_A, which represents the standard deviation index of index A for the test blood sample, according to the following formula: SDI_A = |([index A for the test blood sample] - [mean value of index A for each sample in the normal blood sample group]) / [standard deviation of index A for each sample in the normal blood sample group]| 3. The method of claim 2, further comprising selecting the test blood sample as a blood sample likely to have a coagulation disorder if SDI_A is at or above a predetermined threshold.

4. The method of claim 2, further comprising: obtaining APTTs for the test blood sample and each sample in the group of normal blood samples; calculating SDI_APTT, which represents a standard deviation index of APTTs for the test blood sample, according to the following formula: SDI_APTT = |([APTT for the test blood sample] - [mean APTT for each sample in the normal blood sample group]) / [standard deviation of APTT for each sample in the normal blood sample group]|; and calculating rSDI_A, which represents a ratio of SDI_A to SDI_APTT, according to the following formula: rSDI_A = (SDI_A) / (SDI_APTT).

5. The method of claim 4, further comprising selecting the test blood sample as a blood sample likely to have a coagulation disorder if SDI_A and rSDI_A are at or above a predetermined threshold.

6. The method according to claim 4, wherein the standard deviation of APTT for each sample in said normal blood sample group is 2 seconds or more.

7. The method according to claim 3 or 5, further comprising outputting information indicating the results of said selection for said test blood specimen.

8. The method according to claim 1, wherein the blood sample in which it is not certain that the APTT is prolonged is a sample in which the APTT is within +5 seconds of a predetermined upper limit of the normal range.

9. The method of claim 1, wherein the blood sample is plasma.

10. The method of claim 1, wherein the coagulation abnormality is a coagulation factor deficiency or lupus anticoagulant positivity.

11. The method of claim 10, wherein the coagulation factor is factor VIII, factor IX, or von Willebrand factor.

12. Fs(X) = Ys(X) / Ys(c), and 2. The method of claim 1, wherein 13. The method of claim 1, further comprising: 6) obtaining a parameter Ps(X) based on Rs(i) or Vs(i) for the test blood sample, where i and X are as defined above; and 7) obtaining a parameter Pm(X) for a normal blood sample, where PM j (X) is Rm j (i) or Vm j (i) is a parameter based on the above formula (i), where i, j, k, and X are as defined above; 8) obtaining an index S for the test blood sample based on the following formula (5), (5)', or (5)": where Fs(X) = Ps(X) - Ps(c), and Fm(X) = Pm(X) - Pm(c), or Fs(X) = Ps(X) / Ps(c), and Fm(X) = Pm(X) / Pm(c), a>0, and a≦b, 0<c≦M, and M is the maximum value of X; 9) Ps(X) and Ps(c) in the above formula (5), (5)' or (5)" are respectively set to Pm j (X) and Pm j (c) obtaining an index S for each sample in the normal blood sample group; and (10) comparing the index S for the test blood sample with the statistical value of the index S for each sample in the normal sample group.

14. Ps(X) represents the measurement point or time at which Rs(i) reaches X% of its coagulation reaction end point, and Pm j (X) is Rm j The method according to claim 13, wherein (i) represents the measurement point or time at which the coagulation reaction reaches X% of the end point, and a=3 to 97, b=3 to 97, c=3 to 97, and 0<X≦100.

15. Ps(X) represents the measurement point or time at which Vs(i) reaches X% of its maximum value, provided that if Ps(X) is greater than Ps(100), then Ps(X) is redefined as Ps(200-X), and Pm j (X) is Vm j represents the measurement point or time at which (i) reaches X% of its maximum value, where Pm j (X) is Pm j If it is greater than (100), Pm j (X) is Pm j 14. The method of claim 13, wherein the formula is redefined as (200-X), where a=3 to 98, b=102 to 197, and c=3 to 197.

16. Ps(X) represents the minimum measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to claim 13, wherein (i) represents the minimum value of the measurement point or time at which the value reaches X% of its maximum value, a=3 to 98, b=3 to 98, c=3 to 197, and 0<X≦100.

17. Ps(X) represents the maximum value of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to claim 13, wherein (i) represents the maximum value of the measurement point or time at which X% of the maximum value is reached, a=3 to 98, b=3 to 98, c=3 to 197, and 0<X≦100.

18. Ps(X) represents the midpoint between the minimum and maximum values ​​of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to claim 13, wherein (i) represents the midpoint between the minimum and maximum values ​​of the measurement point or time at which the value reaches X% of its maximum value, a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​≦ 100.

19. Ps(X) represents the length between the minimum and maximum values ​​of the measurement point or time at which Vs(i) reaches X% of its maximum value, and Pm j (X) is Vm j The method according to claim 13, wherein (i) represents the length between the minimum and maximum values ​​of the measurement points or times at which the value reaches X% of the maximum value, and a=3 to 98, b=3 to 98, c=3 to 197, and 0<X<100.

20. Ps(X) represents the weighted average time of Vs(i), and Pm j (X) is Vm j (i) represents a weighted average time, which is calculated according to the following formula (4): In the formula, V(i) is Vs(i) or Vm j (i), t1 and t2 respectively represent the minimum and maximum values ​​of the measurement points or times at which V(i) reaches X% of its maximum value, provided that when V(i) is less than X% of the maximum value, V(i) is considered to be 0, a = 3 to 98, b = 3 to 98, c = 3 to 197, and 0 < X ​​≦ 100.

21. Ps(c) represents the measurement point or time at which Vs(i) reaches c% of its maximum value; PM j (c) is Vm j 14. The method of claim 13, wherein (i) represents the measurement point or time at which c% of its maximum value is reached.

22. The method according to claim 13, wherein step 10) includes calculating SDI_S, which represents the standard deviation index of the index S for the test blood sample, according to the following formula: SDI_S = |([index S for the test blood sample] - [average value of index S for each sample in the normal blood sample group]) / [standard deviation of index S for each sample in the normal blood sample group]| 23. The method of claim 22, further comprising selecting the test blood sample as a blood sample likely to have a coagulation abnormality if: SDI_A is at or above a predetermined threshold, or SDI_A and rSDI_A are at or above a predetermined threshold; and SDI_S is at or above a predetermined threshold.

24. The method of claim 22, further comprising calculating rSDI_S, which represents the ratio of SDI_S to SDI_APTT, according to the following formula: rSDI=SDI_S / SDI_APTT.

25. The method of claim 24, further comprising selecting the test blood sample as a blood sample likely to have a coagulation abnormality if: SDI_A is at or above a predetermined threshold, or SDI_A and rSDI_A are at or above a predetermined threshold; and SDI_S and rSDI_S are at or above a predetermined threshold.

26. The method of claim 23 or 25, further comprising outputting information indicating the results of said selection for said test blood specimen.

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