Psychometric Properties of The 12-Item Stroke-Specific Quality of Life Scale Among Stroke Survivors In Hong Kong

Abstract The present study examined the psychometric properties of the 12-item Stroke-Specific Quality of Life Scale (SSQOL-12) as a measure of quality of life specific to stroke in 184 stroke survivors in Hong Kong. The participants also completed a questionnaire on short form health survey (SF-12) and validating variables at baseline and 148 of them completed SSQOL-12 two months later. Confirmatory factor analysis was performed to investigate the construct validity, reliability, and longitudinal invariance of SSQOL-12 across two months. Convergent and discriminant validity was examined with respect to hope, anxiety, depression, self-esteem, and SF-12. The original 2-factor model did not reveal a superior fit and a modified 1-factor model with 4 residual covariances provided an acceptable fit to data in both waves. The SSQOL-12 factor displayed substantial factor loadings (λ = 0.40–0.87), good reliability (Ω = 0.88), temporal stability (r = 0.70), and scalar measurement invariance across time. Stroke-specific quality of life was significantly associated with ischemic stroke, lower functional disability, anxiety, and depression and higher levels of hope of self-esteem. Most of the associations remained significant after controlling for SF-12. These findings provided support for validity and reliability of the unidimensional structure for SSQOL-12 among stroke survivors.