Development and validation of a self-management ability scale for patients with head and neck cancer undergoing radiotherapy and chemotherapy (SMA-HNC)

Improving self-management is essential for the health of patients with head and neck cancer undergoing radiotherapy and chemotherapy. This study aimed to develop and validate a self-management scale at a preliminary level owing to the lack of standardized assessment tools. A cross-sectional study was conducted to develop the scale through three stages: item generation, item evaluation, and psychometric testing. Content validity was assessed using the content validity index (CVI). Construct validity was evaluated using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Convergent and discriminant validity were examined using average variance extracted (AVE) and composite reliability (CR). Criterion validity was assessed by correlation with the Chinese version of the Strategies Used by People to Promote Health (C-SUPPH) scale. Reliability was evaluated using Cronbach’s α, split-half reliability, and test–retest reliability. After item analysis and factor analysis, the final scale consisted of 6 dimensions and 19 items. Exploratory factor analysis extracted six factors with eigenvalues greater than 1, explaining 71.78% of the total variance. Confirmatory factor analysis supported the six-factor structure with acceptable model fit indices (χ2/df = 2.939, CFI = 0.909, TLI = 0.887, RMSEA = 0.099), and the total variance increased to 79.13%. The scale demonstrated good criterion validity (r = 0.706, P < 0.001). The Cronbach’s α coefficient was 0.906, the split-half reliability was 0.711, and the test–retest reliability was 0.806. The self-management scale for patients with head and neck cancer undergoing radiotherapy and chemotherapy is reliable and valid, serving as a tool for promoting self-management and offering personalized interventions to enhance patient health.