Perceptions of similarity and response to selected comparison targets in type 2 diabetes

Objective: Social comparisons (i.e. self-evaluations relative to others) may affect motivation for diabetes self-care behaviours. Comparisons can have either positive or negative effects, but it is not clear what differentiates these responses. This study tested the effect of a patient’s perceived similarity to a comparison target on motivation for self-care. Design: Individuals with type 2 diabetes (n = 180, M_A1c = 7.59%) selected to read one of four brief descriptions of a patient with diabetes. Main outcome measures: Participants rated their motivation for self-care behaviours prior and subsequent to reading and reported the extent to which they focused on similarities between the self and the selected patient while reading. Results: Perceived similarity moderated the effect of selection on motivation for self-care (p = .01, η²=.06). Increased motivation was observed if participants focused on similarities with patients ‘doing better’ (i.e. high coping effectiveness/low symptom severity) and decreased motivation if they focused on similarities with patients ‘doing worse’ (low coping effectiveness/high symptom severity). Conclusions: Providing social comparison information in diabetes management (and perhaps other chronic diseases) may improve motivation for self-care among some patients. A subset of patients, however, may benefit from guidance to focus on similarities with certain targets.