Psychometric testing of the caregiver contribution to self-care of coronary heart disease inventory

Background: Caregivers are important contributors to the self-care of patients with coronary heart disease (CHD). Aims: The aims of this study are to describe the development and psychometric properties of the caregiver contribution to self-care of coronary heart disease inventory (CC-SC-CHDI). Methods: The CC-SC-CHDI was developed from the patient version of the scale, the Self-care of Coronary Heart Disease Inventory (SC-CHDI) and translated into Italian using forward and backward translation. Baseline data from the HEARTS-IN-DYADS study were used. Confirmatory factor analysis (CFA) was conducted to assess factorial validity; Cronbach's alpha and the model-based internal consistency index were used to test internal consistency reliability, and Pearson's correlation coefficient was used to test convergent validity, by investigating the association between the CC-SC-CHDI and the SC-CHDI scores. Results: We included 131 caregivers (mean age 55 years, 81.2% females, 74% married) of patients affected by CHD (mean age 66 years, 80.2% males, 74% married). The CFA confirmed two factors in the caregiver contribution to self-care maintenance scale ("consulting behaviors" and "autonomous behaviors"), one factor for the CC to self-care monitoring scale, and two factors in the CC to self-care management scale ("consulting behaviors and problem-solving behaviors"). Reliability estimates were adequate for each scale (Cronbach's alpha and model-based internal consistency indexes ranging from 0.73 to 0.90). Significant and positive correlations were observed between CC-SC-CHDI and SC-CHDI scales. Conclusion: The CC-SC-CHDI has satisfactory validity and reliability and can be used confidently in clinical settings and research to assess caregiver contributions to CHD self-care.