Development and testing of a new instrument to measure self-care in patients with osteoporosis: the self-care of osteoporosis scale

Purpose: The aim of this study was to develop and test the Self-Care of Osteoporosis Scale (SCOS), a new instrument to measure self-care in postmenopausal women with osteoporosis. Methods: A cross-sectional study was conducted. The SCOS was developed by a panel of experts and it was theory-driven. Confirmatory factor analysis (N = 544) was used to test the instrument’s factorial validity; Cronbach’s alpha and McDonald’s omega were used to derive the measure’s internal consistency reliability; an intraclass correlation coefficient was used to evaluate test-retest reliability. Results: Confirmatory factor analysis resulted in supportive fit indices for the hypothesized three-factor structure of the SCOS (RMSEA = 0.065; CFI = 0.99). The SCOS was demonstrated to have content validity, internal consistency and test-retest reliability. Conclusions: The SCOS demonstrated excellent psychometric characteristics in terms of validity and reliability. It may be used by healthcare providers to identify if patients show lower self-care and require educational interventions.