Family self-efficacy for diabetes management: Psychometric testing

Background: Type 2 diabetes (T2DM) self-management among adults of Mexican origin occurs in a family context as management is influenced by all family members. Multiple variables, including self-efficacy, affect T2DM self-management behaviors. Reliable and valid instruments exist for measuring an individual's diabetes self-efficacy; however, none are available to measure family self-efficacy. The purpose of this study was to test the psychometric properties of the Family Self- Efficacy for Diabetes Scale (FSE), an 8-item Likert type questionnaire with responses ranging from ‘not at all confident' (1) to ‘totally confident' (5). Methods: Baseline data collected in a larger study were used for analysis. Eighty-eight adults of Mexican origin, 44 with T2DM and 44 family members, completed baseline data. Psychometric analysis included Chronbach's alpha for reliability and principal components factor analysis with an oblimin rotation for construct validity. Concurrent validity was estimated by correlating the FSE with the Diabetes Distress Scale, Family Behaviors Scale, and Family Support for Physical Activity and Healthy Eating Scale. Results: Over half the sample had an income less than $25,000 and less than a high school education. Internal consistency (Cronbach's alpha) was .80. Items loaded on 2 factors – diabetes lifestyle management and diabetes disease management - accounting for 59% of the variance in FSE. FSE significantly correlated negatively with diabetes distress (-.39), and positively with family behaviors (.24) and family support for physical activity (.22,.35) and healthy eating (.23). Conclusions: The FSE is a reliable and valid instrument for PHNs to measure family self-efficacy for diabetes management.