Validity and Reliability of the Self-Care of Chronic Illness Inventory and Self-Care Self-Efficacy Scale in Patients Living With Cancer

Aim: This study aimed to test the psychometric properties of the Self-Care of Chronic Illness Inventory and the Self-Care Self-Efficacy scale in patients with cancer. Design: A multisite cross-sectional validation study was conducted. Methods: Between November 2022 and July 2023, a convenience sample of 318 patients with cancer were enrolled in five Italian inpatient and outpatient facilities. Confirmatory factor analysis was performed on the three scales of the Self-Care of Chronic Illness Inventory and the Self-Care Self-Efficacy scale. Internal consistency was tested using Cronbach's alpha for unidimensional scales and McDonald's Omega for multidimensional scales. Construct validity was assessed with the global health status by Pearson's correlation. The COnsensus-based Standards for the selection of health Measurement INstruments reporting guidelines were followed for the reporting process. Results: Three hundred fourteen patients were included (median age: 55.5 years; male: 53.82%). Confirmatory factor analysis showed supportive fit indices for the three Self-Care of Chronic Illness Inventory scales (CFI: 0.977–1.000; SRMR: 0.004–0.78) and the Self-Care Self-Efficacy scale (CFI: 1.000; SRMR: 0.014). All scales demonstrated adequate internal consistency (0.89–0.99) and test–retest reliability (0.85–0.95). Construct validity was confirmed through correlations between Self-Care Self-Efficacy, each Self-Care of Chronic Illness Inventory scale, and global health status. Conclusion: The Self-Care of Chronic Illness Inventory and Self-Care Self-Efficacy scales demonstrated excellent psychometric qualities and construct validity when administered to patients with cancer. Future research should explore self-care behaviours across different diseases and cultural contexts. Implications For the Profession: These tools can help develop targeted educational programs, improving patient outcomes. Impact: Currently, there is a lack of knowledge regarding self-care behaviours in patients with cancer. These tools enable healthcare professionals to identify patient needs, design personalised interventions, and monitor their effectiveness over time. Patient or Public Contribution: No patient or public contribution.