Method for correcting sensitivity for blood sugar measurement

Abstract

To provide a technology for correcting sensitivity for calculating accurate sensitivity.SOLUTION: A method for correcting sensitivity for blood sugar measurement includes a step for calculating an offset value for sensitivity determination, a step for determining first sensitivity according to a sensing value and reference blood sugar value on the basis of the offset value, and a step for determining sensitivity by adjusting the first sensitivity. The step for determining the sensitivity acquires one sensitivity. The method includes a step for adjusting the one sensitivity to determine sensitivity A by reflecting an average sensing value obtained by averaging a plurality of sensing values and an average blood sugar value obtained by averaging a plurality of blood sugar values to the one sensitivity, and a step for determining the sensitivity A as the sensitivity.SELECTED DRAWING: Figure 12

Description

[Technical field]

[0001] The present embodiment relates to calibrating sensitivity for blood glucose measurement, and more particularly to a sensitivity calibration technique that includes multiple steps of adjusting sensitivity. [Background technology]

[0002] Recently, with the development of medical technology, various medical devices that are attached to the user's body have been developed and sold. The medical devices that are attached to the user's body can be useful for monitoring biological information and treating patients with chronic diseases by attaching them to the skin.

[0003] For example, chronic diseases such as diabetes require continuous management, and a medical device that is attached to the skin to measure blood glucose can be used to monitor the blood glucose of diabetic patients. Diabetes is characterized by having almost no subjective symptoms in the early stages, but as the disease progresses, specific symptoms such as excessive drinking, excessive eating, excessive urination, weight loss, general fatigue, itchy skin, and wounds on the hands and feet that do not heal and remain for a long time appear. As diabetes progresses, complications appear that progress to visual impairment, high blood pressure, kidney disease, paralysis, periodontal disease, muscle spasms and neuralgia, gangrene, etc. In order to diagnose such diabetes and manage it so that it does not progress to complications, it is necessary to perform systematic blood glucose measurement and treatment at the same time.

[0004] For people with diabetes, and those who have not yet developed diabetes but have higher than normal levels of sugar in their blood, many medical device manufacturers offer a variety of blood glucose meters that can measure blood glucose.

[0005] There are two types of blood glucose measuring devices: one in which the user draws blood from the fingertip and measures blood glucose one time, and one in which the device is attached to the user's abdomen, arm, etc. and measures blood glucose continuously.

[0006] Diabetic patients generally alternate between hyperglycemia and hypoglycemia, and emergency situations occur during hypoglycemia, and if they lose consciousness or are not supplied with sugar and the hypoglycemic state continues for a long time, they may even lose their life. Therefore, it is very important for diabetic patients to quickly detect hypoglycemia, but there are limitations to accurately detecting it with blood glucose meters that measure blood glucose intermittently.

[0007] Recently, to overcome these limitations, a Continuous Glucose Monitoring System (CGMS) has been developed and is being used, which is inserted into the human body to measure blood glucose levels every few minutes. The Continuous Glucose Monitoring System can continuously measure blood glucose levels by inserting a needle-shaped transcutaneous sensor into areas such as the abdomen and arms, where pain is relatively low, to minimize the user's pain and discomfort from blood sampling.

[0008] The continuous blood glucose measuring system includes a sensor transmitter that is inserted under the user's skin to measure blood glucose inside the body and transmit the measured blood glucose value, and a terminal that outputs the transmitted blood glucose value.

[0009] Here, since blood glucose measurement is performed with the sensor transmitter attached to the body and part of the sensor inserted in the human body, the sensor inserted in the human body may be recognized as a foreign body. That is, a biological reaction (e.g., hydration reaction) may occur to the sensor. As a result, the sensitivity (slope) may change when the sensor is first inserted. This may reduce the accuracy of the sensor and make it difficult to maintain the expiration date. The changed slope may reduce the accuracy of the continuous blood glucose measurement system by calculating a blood glucose value that is too high or too low for the measured biological signal. In the past, in order to compensate for such a change in sensitivity (slope), a method was developed that uses a simple sensitivity obtained by dividing a reference blood glucose value (blood glucose value measured by a blood glucose monitoring system (BGMS)) input by a user and a current value of the sensor, and a preset offset value, or a method that determines the sensitivity by regression analysis of the reference blood glucose value and the corresponding current value. However, such a method has a problem of providing inaccurate sensitivity and offset values ​​because it does not sensitively respond to abnormal blood glucose values ​​or abnormal operation of the sensor. Summary of the Invention [Problem to be solved by the invention]

[0010] In light of this background, one object of the present embodiment is to provide a technique for calibrating sensitivity in order to calculate accurate sensitivity.

[0011] In light of this background, another object of this embodiment is to provide a technique for providing calibrated sensitivity by adjusting the sensitivity through multiple steps in order to improve the accuracy of the sensitivity. [Means for solving the problem]

[0012] In order to achieve the above object, one embodiment can provide a method for calibrating sensitivity for blood glucose measurement, the method including: calculating an offset value for determining sensitivity; determining a first sensitivity from a sensing value and a reference blood glucose level based on the offset value; and determining the sensitivity by adjusting the first sensitivity, wherein the step of determining the sensitivity includes: acquiring one sensitivity, adjusting the one sensitivity to determine sensitivity A by reflecting an average sensing value obtained by averaging a plurality of sensing values ​​and an average blood glucose value obtained by averaging a plurality of blood glucose values ​​in the one sensitivity; and determining the sensitivity A as the sensitivity.

[0013] Another embodiment can provide a method for calibrating sensitivity for blood glucose measurement, including the steps of: calculating an offset value for determining sensitivity; determining a first sensitivity from a sensing value and a reference blood glucose level based on the offset value; adjusting the first sensitivity to determine sensitivity A by reflecting an average sensing value obtained by averaging a plurality of sensing values ​​over a certain period of time and an average blood glucose value obtained by averaging a plurality of blood glucose values ​​over the certain period of time in the first sensitivity; determining a new sensitivity from sensitivity A depending on whether the blood glucose value calculated from the offset value and the sensitivity A falls within a certain range; and determining the new sensitivity as the sensitivity. Effect of the Invention

[0014] As described above, according to this embodiment, the sensitivity can be calibrated to calculate an accurate sensitivity.

[0015] Furthermore, according to this embodiment, the sensitivity is adjusted through a plurality of steps, thereby making it possible to improve the accuracy of the sensitivity. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram for illustrating a blood glucose measurement system according to an embodiment. [Diagram 2]1 is a diagram illustrating an applicator for attaching a sensor transmitter to a human body according to an embodiment. FIG. [Diagram 3] 11A to 11C are diagrams illustrating a process of attaching a sensor transmitter to a human body using an applicator according to an embodiment. [Figure 4] FIG. 2 is a configuration diagram of a sensor transmitter according to an embodiment. [Diagram 5] FIG. 2 is a configuration diagram of a terminal according to an embodiment. [Figure 6] 1 is a flowchart illustrating a method for calibrating sensitivity according to an embodiment. [Figure 7] 11 is a diagram illustrating an example of adjusting sensitivity based on coding information of a sensor according to an embodiment; FIG. [Figure 8] FIG. 13 is an example diagram illustrating adjusting sensitivity based on a difference from a previously determined sensitivity according to an embodiment. [Figure 9] FIG. 13 is an example diagram illustrating how sensitivity is adjusted based on a certain range formed based on a previous blood glucose value calculated from a reference blood glucose level and a previously determined sensitivity according to an embodiment. [Figure 10] FIG. 13 is an example diagram illustrating how sensitivity is adjusted based on a certain range formed based on a previous blood glucose value calculated from a reference blood glucose level and a previously determined sensitivity according to an embodiment. [Figure 11] FIG. 13 is an example diagram illustrating how sensitivity is adjusted based on a certain range formed based on a previous blood glucose value calculated from a reference blood glucose level and a previously determined sensitivity according to an embodiment. [Figure 12] 10 is a flowchart illustrating a first method for calibrating sensitivity according to another embodiment. [Figure 13] 13 is a flowchart showing a method for adjusting sensitivity based on an average sensing value and an average blood glucose value according to FIG. 12. [Figure 14] FIG. 14 is an exemplary diagram showing an example of adjusting sensitivity based on an average sensing value and an average blood glucose value according to FIG. 13. [Figure 15] 10 is a flowchart illustrating an example of a first method for calibrating sensitivity according to another embodiment. [Figure 16]10 is a flowchart illustrating a second method for calibrating sensitivity according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In the description of the present invention, detailed descriptions of related known functions will be omitted if they are obvious to a person skilled in the art and are deemed to unnecessarily obscure the gist of the present invention.

[0018] The terms used in this application are merely used to describe certain embodiments and are not intended to limit the present invention. A singular expression includes a plural expression unless the context clearly dictates otherwise. In this application, the terms "include" or "have" and the like specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, and are understood not to preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0019] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings. When describing with reference to the accompanying drawings, the same or corresponding components are given the same drawing numbers, and duplicate descriptions thereof will be omitted.

[0020] FIG. 1 is a diagram for illustrating a blood glucose measurement system according to one embodiment.

[0021] Referring to FIG. 1, a blood glucose measuring system 10 (hereinafter referred to as the “system”) according to one embodiment may include a sensor transmitter 100 and a terminal 200.

[0022] The sensor transmitter 100 is attached to a human body B, and when the sensor transmitter 100 is attached to the human body B, one end of the sensor of the sensor transmitter 100 is inserted into the skin so as to periodically extract body fluids from the human body to measure blood glucose.

[0023] The terminal 200 can receive a biosignal including blood glucose information from the sensor transmitter 100, generate blood glucose information from the biosignal, and output the blood glucose information to a user. The terminal 200 can include various devices such as, but is not limited to, a smartphone, a mobile phone, a tablet PC, a desktop, and a laptop, and can include a device having a communication interface capable of communicating with the sensor transmitter 100 and capable of installing programs and applications.

[0024] The sensor transmitter 100 may transmit a measured biosignal to the terminal 200 in response to a request from the terminal 200 or periodically at set times. For data communication between the sensor transmitter 100 and the terminal 200, the sensor transmitter 100 and the terminal 200 may be connected to each other by a wired connection such as a USB cable or may be connected wirelessly by infrared communication, NFC communication, Bluetooth (registered trademark), or the like.

[0025] FIG. 2 is a diagram illustrating an applicator for attaching a sensor transmitter to a human body in one embodiment, and FIG. 3 is a diagram illustrating the process of attaching the sensor transmitter to a human body using an applicator in one embodiment.

[0026] 2 and 3, an applicator 300 according to an embodiment includes a sensor transmitter 100 therein, and is operated to discharge the sensor transmitter 100 to the outside by a user's operation to attach it to a specific body part of the user. The applicator 300 is formed in a shape with one side open, and the sensor transmitter 100 is attached to the applicator 300 via the one open side of the applicator 300.

[0027] When attaching the sensor transmitter 100 to a part of the body using the applicator 300, in order to insert one end of the sensor provided in the sensor transmitter 100 into the skin, the applicator 300 may include a needle (not shown) formed to surround one end of the sensor inside, a first elastic member (not shown) for pushing the needle and one end of the sensor together into the skin, and a second elastic member (not shown) for pulling out only the needle. With such a configuration of the applicator 300, the first elastic member (not shown) arranged in a compressed state inside the applicator 300 is released from compression, so that the needle and one end of the sensor can be inserted into the skin at the same time. When one end of the sensor is inserted into the skin, the compressed second elastic member (not shown) is released from compression, so that only the needle can be pulled out. A user can attach the sensor transmitter 100 to the skin safely and easily through the applicator 300.

[0028] Considering in detail the process of attaching the applicator 300 to the human body B, with the protective cap (not shown) separated, the open side of the applicator 300 is brought into close contact with the skin S of a specific part of the human body B. When the applicator 300 is operated with the applicator 300 in close contact with the skin S of the human body B in this manner, the sensor transmitter 100 can be discharged from the applicator 300 and attached to the skin S. Here, one end of the sensor 101 is disposed at the bottom of the sensor transmitter 100 so as to be exposed from the sensor transmitter 100, and one end of the sensor 101 is partially inserted into the skin S through a needle provided in the applicator 300. Therefore, the sensor transmitter 100 can be attached to the skin S with one end of the sensor 101 inserted into the skin S.

[0029] Here, an adhesive tape may be provided on the surface of the sensor transmitter 100 that comes into contact with the human body B so that the sensor transmitter 100 can be fixedly attached to the skin S of the human body B. Therefore, when the applicator 300 is separated from the skin S of the human body B, the sensor transmitter 100 is fixedly attached to the skin S of the human body B by the adhesive tape.

[0030] Thereafter, when power is applied to the sensor transmitter 100, the sensor transmitter 100 communicates with the terminal, and the sensor transmitter 100 can transmit a biological signal including blood glucose information to the terminal. The sensor transmitter 100 can generate various biological information in addition to blood glucose information, and the following describes a case where blood glucose information is measured as an example of biological information.

[0031] FIG. 4 is a configuration diagram of a sensor transmitter according to an embodiment.

[0032] Referring to FIG. 4, a sensor transmitter 100 according to an embodiment may include a sensor module 110, a sensor communication unit 120, a sensor control unit 130, and a sensor storage unit 140.

[0033] The sensor module 110 may include at least one sensor that is inserted into the human body to sense a biomass. The at least one sensor can measure the biomass and generate a biosignal. The biosignal may include a current value as an analog signal.

[0034] The sensor communication unit 120 can exchange data or information with the terminal. For example, the sensor communication unit 120 can transmit a biological signal transmitted from the sensor module 110 or data stored in the sensor storage unit 140 to the terminal.

[0035] The sensor control unit 130 can control the overall configuration of the sensor transmitter 100, including the sensor module 110, the sensor storage unit 140, and the sensor communication unit 120. For example, the sensor control unit 130 can receive a control signal from a terminal and control the configuration of the sensor transmitter 100 accordingly. The sensor control unit 130 can also process the biosignal. For example, the sensor control unit 130 may convert the biosignal into an analog or digital format, or perform processing to remove noise as necessary.

[0036] Data or information is stored in the sensor storage unit 140. For example, the sensor storage unit 140 may store data on a bioquantity measured by the sensor module 110 (e.g., a current value of a biosignal) or data received from a terminal (e.g., a command value of a control signal).

[0037] FIG. 5 is a configuration diagram of a terminal according to an embodiment.

[0038] Referring to FIG. 5, a terminal 200 according to an embodiment may include an output unit 210, a communication unit 220, a control unit 230, and a storage unit 240.

[0039] The output unit 210 can output the bioinformation (e.g., blood glucose information) included in the biosignal so that the user can check it. For example, the output unit 210 can display the blood glucose information as a numerical value (value), or can display a graph processed from the numerical value.

[0040] The communication unit 220 can communicate with the sensor communication unit of the sensor transmitter to exchange data or information. For example, the communication unit 220 can receive a biological signal including information (biological information) on a biological quantity measured by the sensor transmitter. Here, the communication unit 220 can receive a biological signal that has been primarily processed by the sensor transmitter. Alternatively, the communication unit 220 can transmit a control signal for controlling the sensor transmitter to the sensor transmitter.

[0041] The storage unit 240 may store data or information. For example, the storage unit 240 may store data (e.g., biological information) received from a sensor transmitter. Here, the biological information may include blood glucose information and may have a current value format. Alternatively, the storage unit 240 may store data input by a user or environment setting data for setting the operating environment of the terminal.

[0042] The control unit 230 may include at least one processor that executes a program for calibrating the sensitivity for blood glucose measurement, and at least one memory in which the program is stored. The memory and the processor included in the control unit 230 may be integrated on a single chip, or may be physically separated.

[0043] The memory may be implemented as a non-volatile memory device such as a read only memory (ROM), a programmable ROM (PROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), or a flash memory, or a volatile memory device such as a random access memory (RAM) to store various programs, data, and / or information.

[0044] Meanwhile, the control unit 230 can generate a blood glucose level, which is blood glucose information quantified from the biological information. For this purpose, the control unit 230 may obtain the biological information in the form of a current value from the sensor transmitter, and pre-process and / or process the current value of the biological information. The control unit 230 may first calculate the sensitivity, and generate a blood glucose level according to this sensitivity.

[0045] The control unit 230 can determine the sensitivity based on the current value and an externally input reference blood glucose level, and the sensitivity can be determined by the following Equation 1. Here, C means the current value at the time when the sensitivity is determined based on the reference blood glucose level, i.e., at the time when the sensitivity is calibrated, and BGr is the blood glucose level obtained from a blood glucose monitoring system (BGMS) as the reference blood glucose level, but it does not necessarily have to be obtained at the time when the sensitivity is calibrated.

number

[0046] After the sensitivity is obtained as described above, the control unit 230 can generate a blood glucose value corresponding to the current value by multiplying the current value by the sensitivity. The control unit 230 can provide the new blood glucose value to the user via the output unit 240. For example, the control unit 230 can calculate the sensitivity according to Equation 1 using the first current value acquired at the first time point and one reference blood glucose value, and calculate a new blood glucose value using this sensitivity until the next sensitivity calibration time point (second time point). The control unit 230 can also calibrate the sensitivity again at the second time point. The control unit 230 can calculate the sensitivity according to Equation 1 using the second current value acquired at the second time point and another reference blood glucose value, and calculate a new blood glucose value corresponding to the sensitivity.

[0047] Meanwhile, such sensitivity may change depending on various environmental variables. For example, a fluctuation in current value caused by hydration occurring when the sensor is inserted into a living body, or a negative intercept phenomenon in which the current value continues to decrease (as the bottom value in a biological signal decreases according to the blood glucose level, the baseline also decreases) may be factors that change the sensitivity. When the sensor transmitter transmits a current value that is decreased compared to the conventional case due to the negative intercept phenomenon to the terminal 200, the control unit 230 of the terminal 200 can calculate the sensitivity from a current value smaller than the conventional case according to Equation 1. The sensitivity calculated in this way may become very large. If the control unit 230 calculates the blood glucose level with an excessively high sensitivity, the blood glucose level may become high even for a small current value, and the control unit 230 may generate an inaccurate blood glucose level.

[0048] In order to correct such an error, the control unit 230 may calculate an offset value and reflect the offset value in the calculation of the sensitivity. The control unit 230 may calculate the offset value in various manners without limitation, and the offset value may be fixed or variable. The control unit 230 may determine the sensitivity reflecting the offset value according to the following Equation 2. Here, Voff is the offset value, and may be a value preset by the user or may be a value that is variable according to an algorithm of the storage unit 240.

number

[0049] In the above example, the decrease in the current value due to the negative intercept phenomenon is offset by the offset value, the smaller denominator becomes larger, and the sensitivity can change to an appropriate level that is not excessive. However, the control unit 230 of the terminal 200 according to an embodiment may not immediately use the sensitivity reflecting the offset value in calculating the blood glucose level, but may adjust the sensitivity and then use the adjusted sensitivity in calculating the blood glucose level. Hereinafter, a method for calibrating the sensitivity through multiple steps of adjusting the sensitivity by the control unit 230 of the terminal 200 will be described.

[0050] FIG. 6 is a flowchart showing a method for calibrating sensitivity according to an embodiment, FIG. 7 is an example diagram of adjusting sensitivity based on coding information of a sensor according to an embodiment, FIG. 8 is an example diagram of adjusting sensitivity based on a difference from a previously determined sensitivity according to an embodiment, and FIGS. 9 to 11 are example diagrams of adjusting sensitivity based on a certain range formed based on a previous blood glucose value calculated from a reference blood glucose level and a previously determined sensitivity according to an embodiment.

[0051] 6, a method for calibrating sensitivity in a terminal constituting a blood glucose measurement system according to an embodiment is illustrated. Hereinafter, sensitivity calibration is described as being performed in the terminal, but is not limited thereto, and may be performed in a sensor transmitter or a host (e.g., a server) connected to the terminal via a wired or wireless network depending on the configuration. A control unit of the terminal first determines a sensitivity required to generate a blood glucose value from a current value, and finally applies the current value to the determined sensitivity to generate a blood glucose value.

[0052] For this reason, the control unit of the terminal can first calculate an offset value for determining the sensitivity (step S601). The offset value may be a value that compensates for the change in sensitivity due to a decrease in the current value.

[0053] The control unit can also determine the sensitivity from the current value reflecting the offset value and the reference blood glucose level according to Equation 2 (step S603). The sensitivity determined here may not be the final sensitivity, but may simply be the sensitivity reflecting only the offset value before the adjustment step. Hereinafter, for convenience of explanation, such sensitivity will be referred to as the "first sensitivity." Also, the current value is a type of value measured by a sensor included in the sensor module, and may also be referred to as a sensing value.

[0054] First, an adjustment may be made to the first sensitivity. The control unit of the terminal may determine a second sensitivity from the first sensitivity and a sensitivity preset by the sensor (step S605). The sensitivity preset by the sensor may be a sensitivity preset for any sensor, or may be a sensitivity preset for any group (lot) that is a collection of multiple sensors. The sensitivity for the sensors of one group may be understood as a specific sensitivity that represents not one sensor but an entire group. Hereinafter, for convenience of explanation, the sensitivity preset by the sensor may be referred to as the "sensor sensitivity".

[0055] Here, the sensor sensitivity may include an ideal sensitivity expected from a sensor or a group of sensors under ideal conditions. For example, the sensor sensitivity may be understood as a sensitivity that a sensor or a group of sensors should have under ideal conditions, such as a laboratory environment. Alternatively, the sensor sensitivity may be understood as a sensitivity that is preset in a factory when manufacturing a sensor or a group of sensors. When using a terminal, coding is required for initialization, and the sensor sensitivity may be included in coding information during the coding process and input and / or stored in the terminal.

[0056] 7, an example of determining a second sensitivity from a first sensitivity and a sensor sensitivity is illustrated. The control unit of the terminal may reflect the sensor sensitivity to adjust the first sensitivity, and determine the second sensitivity as a result. However, the control unit of the terminal may reflect the sensor sensitivity differently in some cases.

[0057] First, the control unit may compare the first sensitivity with the sensor sensitivity. If the first sensitivity is greater than the sensor sensitivity, the control unit may determine the sensor sensitivity as the second sensitivity. For example, in this drawing, if the first sensitivity (S1) is 25 at the first calibration point in time P1 and the sensor sensitivity (Ss), which is the sensitivity according to the coding information, is 20, the control unit may determine the second sensitivity (S2) to be 20. Hereinafter, units will be omitted for convenience of explanation. The control unit may determine the sensor sensitivity (Ss) as the second sensitivity (S2) by being more reliable.

[0058] Otherwise, that is, if the first sensitivity is smaller than the sensor sensitivity, the control unit may process the sensor sensitivity and determine the processed second sensitivity as the first sensitivity. For example, in this drawing, if the first sensitivity (S1) is 5 at the second calibration point P2 and the sensor sensitivity (Ss), which is the sensitivity according to the coding information of the sensor, is 20, the control unit may process the sensor sensitivity (Ss) to calculate a value corresponding to 1 / 3 of the sensor sensitivity (Ss), and determine 20 / 3 (≒6.7), which is a value corresponding to 1 / 3 of the sensor sensitivity (Ss), as the second sensitivity (S2). The control unit may be more reliable in the sensor sensitivity (Ss) and determine the processed value of the sensor sensitivity (Ss) as the second sensitivity (S2).

[0059] When the first sensitivity is the same as the sensor sensitivity, the control unit may determine the first sensitivity as the second sensitivity as it is.

[0060] Returning to FIG. 6, an adjustment may be made to the second sensitivity. The control unit of the terminal may determine a third sensitivity by adjusting the second sensitivity based on the reliability of the first sensitivity based on the difference between the first sensitivity and a previously determined sensitivity (step S607). Here, the previously determined sensitivity may refer to the final sensitivity at a previous point in time, and the previous point in time may refer to a specific point in time in the past before the current point in time at which the sensitivity is to be calibrated. The control unit of the terminal may have calculated the blood glucose level at a previous point in time according to the previously determined sensitivity. Hereinafter, for convenience of explanation, this may be referred to as the "previous sensitivity."

[0061] Specifically, if the first sensitivity is higher or lower than the previous sensitivity consecutively (at least twice or more), the control unit of the terminal can determine that the first sensitivity is reliable and that the reliability of the first sensitivity is high. After that, the control unit may calculate a combined sensitivity that reflects the first sensitivity and the second sensitivity, and determine this combined sensitivity as the third sensitivity. The control unit can calculate the combined sensitivity by averaging the first sensitivity and the second sensitivity.

[0062] Referring to FIG. 8, an example of determining the third sensitivity by adjusting the second sensitivity is shown. For example, in this drawing, if the first sensitivity (S1) is 30 and the previous sensitivity (Sp) is 25 at the first calibration time point P1, and the first sensitivity (S1) is 32 and the previous sensitivity (Sp) is 27 at the second calibration time point P2, the first sensitivity (S1) has a higher value than the previous sensitivity (Sp) at two consecutive calibration times, so the control unit can determine that the reliability of the first sensitivity (S1) having 29 at the third calibration time point P3 is high. Thus, at the third calibration time point P3, the control unit can calculate the binding sensitivity from the first sensitivity (S1) 29 and the second sensitivity (S2) 25. The control unit can calculate the average value of the first sensitivity (S1) 29 and the second sensitivity (S2) 25, 27 (=(29+25) / 2), as the binding sensitivity. The control unit may determine the binding sensitivity 27 as the third sensitivity (S3).

[0063] In this way, if the first sensitivity is successively higher or lower, the first sensitivity can be deemed valid, and unlike step S605, it is preferable that the first sensitivity is more reflected than the second sensitivity.

[0064] Returning to FIG. 6, the third sensitivity may be adjusted. The control unit of the terminal may calculate the blood glucose level from the offset value and the third sensitivity, and determine the fourth sensitivity from the third sensitivity depending on whether the calculated blood glucose level falls within a certain range. If the calculated blood glucose level falls within the certain range, the control unit may regard the third sensitivity as appropriate and determine the third sensitivity as the fourth sensitivity as it is. Otherwise, the control unit may regard the third sensitivity as inappropriate, calculate an adjusted sensitivity instead of the third sensitivity, and determine the adjusted sensitivity as the fourth sensitivity.

[0065] Here, the certain range can be specified based on the previous blood glucose level and the reference blood glucose level. The control unit can calculate the previous blood glucose level from the current value at the current time point, the previous sensitivity, and a previously calculated offset value (previous offset value). The control unit can also obtain the reference blood glucose level (the reference blood glucose level used to determine the first sensitivity in step S601) from outside. The control unit can determine whether the blood glucose level calculated from the current value at the current time point, the offset value at the current time point, and the third sensitivity is within the range defined by the previous blood glucose level and the reference blood glucose level.

[0066] 9, an example is shown in which the fourth sensitivity is determined from the third sensitivity depending on whether the blood glucose level calculated from the third sensitivity falls within a certain range. In one example, it can be assumed that the control unit determines the fourth sensitivity at a first calibration point P1. First, the control unit can determine the validity of the third sensitivity by specifying a certain range.

[0067] If the current value (C) at the first calibration time point P1 is 7, the previous sensitivity (Sp) is 20, and the previous offset value (Voff_p) is 0, the previous blood glucose value (BGp) is 140 (=(7-0)×20). Here, the previous sensitivity (Sp) and the previous offset value (Voff_p) may be the sensitivity and offset value determined before the sensitivity calibration is performed at the first calibration time point P1. If the reference blood glucose value (BGr) is 200 at the first calibration time point P1, the blood glucose value range for which the blood glucose value according to the third sensitivity is valid, i.e., a certain range determined based on the previous blood glucose value and the reference blood glucose value, corresponds to 140 to 200.

[0068] Furthermore, since the current value (C) at the first calibration point in time P1 is 7, the offset value (Voff) at the first calibration point in time P1 is 0, and the third sensitivity (S3) is 30, the control unit can use these to calculate the blood glucose level (BG) of 210 (=(7-0)×30). Since the blood glucose level (BG) is 210, which falls outside the certain range of 140 to 200, the control unit considers the third sensitivity (S3) to be invalid and can calculate an adjustment sensitivity to determine the fourth sensitivity.

[0069] The control unit can calculate the adjustment sensitivity from the (current) current value, the (current) offset value, the previous blood glucose value, and the reference blood glucose value using the following Equation 3.

number

[0070] According to this example, the current value (C) at the first calibration point P1 is 7, the offset value (Voff) at the first calibration point P1 is 0, the previous blood glucose level (BGp) is 140, and the reference blood glucose level (BGr) is 200, so the adjustment sensitivity (Sa) is 24.29. The control unit may determine the adjustment sensitivity (Sa) as the fourth sensitivity. The control unit may determine 24.29 as the fourth sensitivity.

[0071] 10, another example is shown in which the fourth sensitivity is determined from the third sensitivity depending on whether the blood glucose level calculated from the third sensitivity falls within a certain range. In another example, it can be assumed that the control unit determines the fourth sensitivity at the second calibration point P2. First, the control unit can determine the validity of the third sensitivity by specifying a certain range.

[0072] If the current value (C) at the second calibration point P2 is 5, the previous sensitivity (Sp) is 30, and the previous offset value (Voff_p) is 1, the previous blood glucose value (BGp) is 120 (=(5-1)×30). Here, the previous sensitivity (Sp) and the previous offset value (Voff_p) may be the sensitivity and offset value determined before the sensitivity calibration is performed at the second calibration point P2. If the reference blood glucose value (BGr) is 140 at the second calibration point P2, the blood glucose value range for which the blood glucose value according to the third sensitivity is valid, i.e., a certain range determined based on the previous blood glucose value and the reference blood glucose value, corresponds to 120 to 140.

[0073] Furthermore, since the current value (C) at the second calibration point in time P2 is 5, the offset value (Voff) at the second calibration point in time P2 is 0.5, and the third sensitivity (S3) is 28, the control unit can use these to calculate the blood glucose level (BG) to be 126 (=(5-0.5)×28). Since the blood glucose level (BG) is 126, which falls within a certain range of 120 to 140, the control unit may regard the third sensitivity (S3) as valid and determine it to be the fourth sensitivity. Therefore, in this example, the fourth sensitivity is 28.

[0074] 11, another example is shown in which the fourth sensitivity is determined from the third sensitivity depending on whether the blood glucose level calculated from the third sensitivity falls within a certain range. In another example, it can be assumed that the control unit determines the fourth sensitivity at the third calibration point P3. First, the control unit can specify a certain range and determine the validity of the third sensitivity.

[0075] If the current value (C) at the third calibration point P3 is 12, the previous sensitivity (Sp) is 25, and the previous offset value (Voff_p) is 0.5, the previous blood glucose value (BGp) is 287.5 (=(12-0.5)×25). Here, the previous sensitivity (Sp) and the previous offset value (Voff_p) may be the sensitivity and offset value determined before the sensitivity calibration is performed at the third calibration point P3. If the reference blood glucose value (BGr) is 200 at the third calibration point P3, the blood glucose value range for which the blood glucose value according to the third sensitivity is valid, i.e., a certain range determined based on the previous blood glucose value and the reference blood glucose value, corresponds to 200 to 287.5.

[0076] Furthermore, because the current value (C) at the third calibration point P3 is 12, the offset value (Voff) at the third calibration point P3 is 0.3, and the third sensitivity (S3) is 15, the control unit can use these to calculate a blood glucose level (BG) of 175.5 (=(12-0.3)×15). Because the blood glucose level (BG) is 175.5, which falls outside the certain range of 200 to 287.5, the control unit considers the third sensitivity (S3) to be invalid and can calculate an adjustment sensitivity to determine the fourth sensitivity.

[0077] The control unit can calculate the adjustment sensitivity from the (current) current value, (current) offset value, previous blood glucose value, and reference blood glucose value using the above-mentioned Equation 3. According to this example, the current value (C) at the third calibration point in time P3 is 12, the offset value (Voff) at the third calibration point in time P3 is 0.3, the previous blood glucose value (BGp) is 287.5, and the reference blood glucose value (BGr) is 200, so the adjustment sensitivity (Sa) is 20.33. The control unit may determine 20.33 as the fourth sensitivity.

[0078] FIG. 12 is a flow chart showing a first method for calibrating sensitivity according to another embodiment.

[0079] Referring to FIG. 12, a first method of calibrating sensitivity in a terminal constituting a blood glucose measurement system according to another embodiment is illustrated. The following is not limited thereto, and depending on the configuration, the method may be performed in a sensor transmitter or a host (e.g., a server) connected to the terminal via a wired or wireless network. A control unit of the terminal may first determine a sensitivity required to generate a blood glucose value from a current value, and finally generate a blood glucose value by applying the current value to the determined sensitivity. In addition, the other embodiment includes the same configuration as the first embodiment, and the description of the first embodiment is applied as it is, and the following description will be focused on the differences, omitting the description of the common parts with the first embodiment.

[0080] First, the control unit of the terminal may calculate an offset value for determining the sensitivity (step S1201). The offset value may be a value that compensates for a change in sensitivity due to a decrease in the current value.

[0081] In addition, the control unit can determine the sensitivity from the current value reflecting the offset value and the reference blood glucose level using Equation 2 (step S1203). The sensitivity determined here is the "first sensitivity" and is not the final sensitivity, but may simply be the sensitivity reflecting only the offset value before the adjustment step.

[0082] Then, an adjustment may be made to the first sensitivity. The control unit of the terminal may finally determine the sensitivity by adjusting the first sensitivity (step S1205). In order to finally determine the sensitivity from the first sensitivity, the control unit of the terminal may perform the following detailed adjustment.

[0083] Specifically, the control unit of the terminal can adjust the first sensitivity based on an average sensing value obtained by averaging a plurality of sensing values ​​and an average blood glucose value obtained by averaging a plurality of blood glucose values ​​(step S1205-1). Here, when the first sensitivity is adjusted based on an average sensing value obtained by averaging a plurality of sensing values ​​and an average blood glucose value obtained by averaging a plurality of blood glucose values, the adjusted first sensitivity may be referred to as "sensitivity A."

[0084] The control unit of the terminal may determine the sensitivity A as the adjusted first sensitivity, that is, the final sensitivity that the control unit of the terminal is to obtain (step S1205-2). Hereinafter, the step of determining the sensitivity A will be specifically considered.

[0085] FIG. 13 is a flowchart showing a method for adjusting sensitivity based on the average sensing value and average blood glucose value according to FIG. 12, and FIG. 14 is an exemplary diagram showing a method for adjusting sensitivity based on the average sensing value and average blood glucose value according to FIG.

[0086] Referring to FIG. 13, a method for adjusting the sensitivity based on the average sensing value and the average blood glucose value, i.e., a method for determining the sensitivity A, according to another embodiment is illustrated.

[0087] The control unit of the terminal can generate the first sensitivity from Equation 2 (step S1301). The control unit of the terminal can also obtain an average sensing value and an average blood glucose value (step S1303). The average sensing value may mean a value obtained by averaging the sensing values ​​measured by the sensor up to the current time point at which the sensitivity is calibrated. The start time point of the average may be the time point at which the sensor is inserted, or may be any time point before the current time point preset by the user. The sensing values ​​from that time point to the current time point can be averaged. The average blood glucose value may mean a value obtained by averaging the blood glucose values ​​calculated by the blood glucose measurement system up to the current time point at which the sensitivity is calibrated. The start time point of the average is determined in the same manner as the average sensing value, and the blood glucose values ​​from that time point to the current time point can be averaged.

[0088] Then, the control unit of the terminal can calculate the average sensitivity by applying a first weight to the first sensitivity, the average sensing value, and the average blood glucose value (step S1305). A first weight is assigned to each of the first sensitivity, the average sensing value, and the average blood glucose value, and each of the first weights can change over time. For example, the control unit of the terminal can apply a weight 1a to the first sensitivity, a weight 1b to the average sensing value, and a weight 1c to the average blood glucose value. By adjusting the weights 1b and 1c, the ratio reflected in the first sensitivity can be increased or decreased.

[0089] Also, the control unit of the terminal may calculate the difference between the first sensitivity and the average sensitivity, and determine whether the difference exceeds a certain range (step S1307). If the difference exceeds the certain range, the control unit of the terminal may use the average sensitivity instead of the first sensitivity to determine sensitivity A from the average sensitivity (YES in step S1307 and step S1309). If the first sensitivity is too far from the average sensitivity, the average sensitivity is used. The control unit of the terminal may apply a second weight to the average sensitivity to determine it as sensitivity A. Sensitivity A is determined as the final sensitivity, and the control unit of the terminal may calculate the blood glucose level for the current value using sensitivity A (step S1311).

[0090] If the difference does not exceed a certain range, the control unit of the terminal may determine the first sensitivity as sensitivity A without using the average sensitivity (NO in step S1307 and step S1313). Sensitivity A is determined as the final sensitivity, and the control unit of the terminal can calculate the blood glucose level for the current value using sensitivity A (step S1315).

[0091] 16, an example of adjusting sensitivity based on an average sensing value and an average blood glucose value according to another embodiment is illustrated. In this figure, a current value corresponding to the sensing value, an average current value corresponding to the average sensing value, and an average blood glucose value are illustrated.

[0092] The first calibration point P1 may be the current point in time, and may be the point in time at which the control unit of the terminal attempts to calculate the final sensitivity to calculate the blood glucose level. At the first calibration point P1, the control unit of the terminal may obtain a first sensitivity (S1) of 20. In addition, the control unit of the terminal may calculate an average sensitivity (Savg) of 30 by applying a first weight to the average sensing value, the average blood glucose level, and the first sensitivity (S1).

[0093] Also, the control unit of the terminal may determine the sensitivity A based on the average sensitivity (Savg). Specifically, the control unit of the terminal may calculate the difference (Diff) between the first sensitivity (S1) and the average sensitivity (Savg). The difference (Diff) may be expressed as a ratio of the difference between the first sensitivity (S1) and the average sensitivity (Savg) to the average sensitivity (Savg), and when the above numerical value is applied, the difference (Diff) is 33.3%. It may be determined that the difference (Diff) deviates from a certain range (for example, the certain range is 20%). The certain range may be the same concept as a preset critical value. Thus, the average sensitivity (Savg) may be used to determine the sensitivity A, and a second weight may be applied to the average sensitivity (Savg). The second weight is set to 0.85, and the sensitivity A is 25.5. Here, the second weight may be changed so as to increase with the passage of time. As a result, the ratio at which the average sensitivity (Savg) is reflected in the sensitivity A may increase. This is because the average sensitivity (Savg), which reflects past trends, may be more accurate as time passes.

[0094] FIG. 15 is a flowchart illustrating an example of a first method for calibrating sensitivity according to another embodiment.

[0095] 15, a first method for calibrating sensitivity according to another embodiment may include at least a part of the sensitivity calibrating step described in the first embodiment. An example is shown in which the first method includes a step of calibrating sensitivity depending on whether a blood glucose level calculated from an offset value and one sensitivity falls within a certain range.

[0096] An offset value for determining the sensitivity can be calculated (step S1501). The offset value may be a value that compensates for a change in sensitivity due to a decrease in the current value.

[0097] In addition, the control unit can determine the first sensitivity from the current value reflecting the offset value and the reference blood glucose level using Equation 2 (step S1503).

[0098] Then, an adjustment to the first sensitivity may be performed. The control unit of the terminal can finally determine the sensitivity by adjusting the first sensitivity (step S1505). In order to finally determine the sensitivity from the first sensitivity, the control unit of the terminal can adjust the first sensitivity in detail as follows.

[0099] The control unit of the terminal can determine the sensitivity A by adjusting the first sensitivity based on an average sensing value obtained by averaging a plurality of sensing values ​​and an average blood glucose value obtained by averaging a plurality of blood glucose values ​​(step S1505-1).

[0100] In addition, the control unit of the terminal may determine a fourth sensitivity from the sensitivity A depending on whether the blood glucose level calculated from the offset value and the sensitivity A falls within a certain range (step S1505-2). Determining the fourth sensitivity may be the same as that described above in one embodiment.

[0101] The control unit of the terminal may determine either one of the sensitivity A and the fourth sensitivity as the adjusted first sensitivity, i.e., the final sensitivity that the control unit of the terminal is to obtain (step S1505-3). Here, in step S1505-1, the control unit of the terminal may calculate the sensitivity A, and in step S1505-2, may determine the fourth sensitivity based on the sensitivity A. The control unit of the terminal may determine either one of the sensitivity A and the fourth sensitivity as the final sensitivity for calculating the blood glucose level from the current value. The control unit of the terminal may determine the sensitivity by adjusting the first sensitivity in steps S1505-1 to S1505-3.

[0102] FIG. 16 is a flow chart illustrating a second method for calibrating sensitivity according to another embodiment.

[0103] 16, a second method for calibrating the sensitivity in a terminal constituting a blood glucose measurement system according to another embodiment is shown. In the first method, each step of determining the fourth sensitivity from the sensitivity A and the second sensitivity can be applied selectively or in parallel, while in the second method, each step can be applied in series to have one procedure.

[0104] Specifically, an offset value for determining the sensitivity can be calculated (step S1601). The offset value may be a value that compensates for a change in sensitivity due to a decrease in the current value.

[0105] Furthermore, the control unit can determine the first sensitivity from the current value reflecting the offset value and the reference blood glucose level using Equation 2 (step S1603).

[0106] In addition, the control unit of the terminal can acquire the first sensitivity, and adjust the first sensitivity based on an average sensing value obtained by averaging multiple sensing values ​​and an average blood glucose value obtained by averaging multiple blood glucose values, to determine sensitivity A (step S1605).

[0107] Furthermore, the control unit of the terminal acquires sensitivity A, and can determine a fourth sensitivity from sensitivity A depending on whether the blood glucose level calculated from the offset value and sensitivity A falls within a certain range (step S1607).

[0108] Furthermore, the control unit of the terminal may determine the fourth sensitivity as the final sensitivity (step S1609).

[0109] Aspects of the subject matter described herein may be described in the context of computer-executable instructions, such as program modules, being executed on a computer. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform particular tasks or particular abstract data types.

[0110] Alternatively or additionally, the functions described herein may be performed, at least in part, by one or more hardware logic components. By way of example and not limitation, exemplary types of hardware logic components that may be used include field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), system-on-a-chip systems (SOCs), complex programmable logic devices (CPLDs), and the like.

[0111] Meanwhile, the disclosed embodiments may be embodied as a recording medium storing a program and / or instructions executable by a computer. The instructions may be stored in the form of program code, and when executed by a processor, may generate a program module and perform the operations of the disclosed embodiments. The recording medium may be embodied as a computer-readable recording medium.

[0112] The computer-readable recording medium includes any type of recording medium in which computer-readable instructions are stored, such as read only memory (ROM), random access memory (RAM), magnetic tape, magnetic disk, flash memory, optical data storage device, etc.

[0113] Although one embodiment of the present invention has been described above, a person having ordinary knowledge in the art may modify and change the present invention in various ways by adding, changing or deleting components without departing from the concept of the present invention described in the claims, and this may also be said to be within the scope of the present invention.

Claims

1. Calculating an offset value for determining sensitivity; determining a first sensitivity from the sensed value and the reference blood glucose value based on the offset value; determining a sensitivity by adjusting the first sensitivity; Including, The step of determining the sensitivity comprises: A step of acquiring one sensitivity, and adjusting the one sensitivity to reflect an average sensing value obtained by averaging a plurality of sensing values ​​and an average blood glucose value obtained by averaging a plurality of blood glucose values ​​in the one sensitivity, thereby determining a sensitivity A; determining said sensitivity A as said sensitivity; A method for calibrating sensitivity for blood glucose measurement, comprising:

2. The step of determining the sensitivity A comprises: calculating an average sensitivity by applying a first weight to the average sensing value, the average blood glucose value, and the one sensitivity; determining the sensitivity A based on the average sensitivity; The method for calibrating sensitivity for blood glucose measurement according to claim 1 , comprising:

3. 3. The method of calibrating sensitivity for blood glucose measurement according to claim 2, wherein the step of determining the sensitivity A based on the average sensitivity determines the result of applying a second weight to the average sensitivity as the sensitivity A when the difference between the one sensitivity and the average sensitivity falls outside a certain range.

4. 4. The method of calibrating sensitivity for blood glucose measurement according to claim 3, wherein the second weight increases over time to increase the ratio of reflection of the average sensitivity to the sensitivity A.

5. The step of determining the sensitivity further includes a step of acquiring another sensitivity, and determining a new sensitivity from the other sensitivity depending on whether the blood glucose level calculated from the offset value and the other sensitivity falls within a certain range; 2. The method for calibrating sensitivity for blood glucose measurement according to claim 1, wherein the step of determining the sensitivity A as the sensitivity determines either the sensitivity A or the new sensitivity as the sensitivity.

6. calculating an offset value for determining the sensitivity; determining a first sensitivity from the sensed value and the reference blood glucose value based on the offset value; determining sensitivity A by adjusting the first sensitivity based on an average sensing value obtained by averaging a plurality of sensing values ​​over a certain period of time and an average blood glucose value obtained by averaging a plurality of blood glucose values ​​over the certain period of time; determining a new sensitivity from the sensitivity A depending on whether the blood glucose level calculated from the offset value and the sensitivity A falls within a certain range; determining the new sensitivity as the sensitivity; A method for calibrating sensitivity for blood glucose measurement, comprising:

Images