Psychometric evaluation of the Chinese version of the subjective happiness scale: Evidence from the Hong Kong FAMILY cohort

Abstract

BACKGROUND: With China's rapid economic growth in the past few decades, there is currently an emerging focus on happiness. Cross-cultural validity studies have indicated that the four-item Subjective Happiness Scale (SHS) has high internal consistency and stable reliability. However, the psychometric characteristics of the SHS in broader Chinese community samples are unknown. PURPOSE: We evaluated the factor structure and psychometric properties of the SHS in the Hong Kong general population. METHODS: The Chinese SHS was derived using forward-backward translation. Of the Cantonese-speaking participants aged >/=15 years, 2,635 were randomly selected from the random sample component of the FAMILY Cohort, a territory-wide cohort study in Hong Kong. In addition to the SHS, a single-item overall happiness scale, the Patient Health Questionnaire-9 (PHQ-9), the Family Adaptation, Partnership, Growth, Affection, Resolve (APGAR) scale, and the Medical Outcomes Study 12-item short-form version 2 (SF-12) mental and physical health scales were administered. RESULTS: Exploratory and confirmatory factor analyses supported a single factor with high loadings for the four SHS items. Multiple group analyses indicated factor invariance across sex and age groups. Cronbach's alpha was 0.82, and 2-week test-retest reliability (n = 191) was 0.70. The SHS correlated significantly with single-item overall happiness (Spearman's rho [rho] = 0.57), Family APGAR (rho = 0.26), PHQ-9 (rho = -0.34), and mental health-related quality of life (rho = 0.40) but showed a lower correlation with physical health (rho = 0.15). A regression model that included the PHQ-9 and Family APGAR scores explained 37 % of the variance in SF-12 mental health scores; adding the SHS raised the variance explained to 41 %. CONCLUSIONS: Our results support the reliability and validity of the SHS as a relevant component in the measurement battery for mental well-being in a Chinese general population.