Validity and reliability of the Japanese Adult Social Care Outcomes Toolkit four-level Self Completion Tool (ASCOT SCT4) in community mental health service users in Japan

Outcome evaluations using patient-reported outcome measures (PROMs) are becoming increasingly important in healthcare, including long-term care and disability support. The Adult Social Care Outcomes Toolkit (ASCOT) is a self-reported measure that assesses social care-related quality of life (SCRQoL), which can be affected by long-term care services. This study examined the validity and reliability of the Japanese ASCOT four-level Self-Completion Tool (SCT4) for people with mental illnesses who used community services. We conducted a cross-sectional survey of persons with mental illnesses who used community services in 22 facilities across Japan. Confirmatory factor analysis (CFA) was performed to confirm the factor structure. Spearman’s rank correlation coefficients were calculated to assess the convergent validity of health-related quality of life (HRQoL), personal agency, well-being, depressive symptoms, functional assessment, and objective quality of life (QoL). Cronbach’s alpha and intra-class correlation coefficients (ICC) were computed to assess internal consistency and test-retest reliability, respectively. In total, 397 service users agreed to participate, and 64 completed the Japanese ASCOT SCT4 twice to assess test-retest reliability. The model fit indices indicated chi-squared statistic /degrees of freedom (CMIN/df) = 1.069 (p = 0.375), root mean square error of approximation (RMSEA) = 0.013, standardized root mean square residual (SRMR) = 0.026, comparative fit index (CFI) = 0.998, and Tucker-Lewis index (TLI) = 0.997. The Japanese ASCOT SCT4 demonstrated significant correlations with HRQoL (ρ = 0.619, p < 0.001), personal agency (ρ = 0.502, p < 0.001), well-being (ρ = 0.657, p < 0.001), depressive symptoms (ρ = -0.657, p < 0.001), and functional assessment (self-reported version: ρ = -0.616, p < 0.001; observer-reported version: ρ = -0.242, p < 0.001), and objective QoL (ρ = 0.240, p < 0.001). Cronbach’s alpha and ICC were 0.76 and 0.71, respectively. The Japanese ASCOT SCT4 can be potentially useful as a PROM to easily assess the SCRQoL of individuals with mental illness who use community services. Future studies should use additional validity tests with more diverse samples.