Methods and systems are described for diagnosis and / or treatment of physical or mental conditions, disorders, disabilities or illnesses, injuries, and chronic conditions. According to one embodiment, a communications network that provides a closed communication service to facilitate and encourage affective communication, activity stimulating communication and / or intellectually stimulating communication among members of a caregroup and a target of the caregroup is used as a method of treatment for (i) a physical or mental condition, disorder, disability or illness, (ii) an injury, and / or (iii) a chronic condition of the target. According to another embodiment, such a closed communication service is used as a method of facilitating (i) diagnosis of the target's mental or physical status, (ii) evaluation of the target's response to service stimuli and treatments and condition over time; and / or (iii) making prognoses regarding progression of physical or mental condition, disability, disease or chronic conditions of the target.