Measuring self-care in the general adult population: development and psychometric testing of the Self-Care Inventory

BACKGROUND: Self-care is important at all stages of life and health status to promote well-being, prevent disease, and improve health outcomes. Currently, there is a need to better conceptualize self-care in the general adult population and provide an instrument to measure self-care in this group. Therefore, the aim of this study was to develop and evaluate the Self-Care Inventory (SCI), a theory-based instrument to measure self-care in the general adult population. METHODS: Based on the Middle Range Theory of Self-Care, the 20-item SCI was developed with three scales: Self-Care Maintenance (8 items), Self-Care Monitoring (6 items), and Self-Care Management (6 items). A cross sectional study with a US-based sample (n = 294) was conducted to test the SCI. Internal validity was assessed with Confirmatory Factor Analysis. Internal consistency reliability was assessed with Cronbach alpha for unidimensional scales or composite reliability and the global reliability index for multidimensional scales. Construct validity was investigated with Pearson correlation to test the relationship between general self-efficacy, positivity, stress, and self-care scores. RESULTS: The Self-Care Maintenance and Management scales were multidimensional and the Self-Care Monitoring scale was unidimensional. The global reliability index for multidimensional scales was 0.85 (self-care maintenance) and 0.88 (self-care management). Cronbach alpha coefficient of the self-care monitoring scale was 0.88. Test-retest reliability was 0.81 (self-care maintenance), 0.91 (self-care monitoring), and 0.76 (self-care management). The General Self-Efficacy Scale was positively related to all three self-care scale scores: self-care maintenance r = 0.46, p < 0. 001, self-care monitoring r = 0.31, p < 0. 001, and self-care management r = 0.32, p < 0. 001. The positivity score was positively related to self-care maintenance (r = 0.42, p < 0. 001), self-care monitoring (r = 0.29, p < 0. 001), and self-care management (r = 0.34, p < 0. 001) scores. The perceived stress was positively related to the self-care management (r = 0.20, p < 0. 001) score. CONCLUSIONS: The SCI is a theoretically based instrument designed to measure self-care in the general adult population. Preliminary evidence of validity and reliability supports its use in the general adult population.