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

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 [ρ]∈=∈0.57), Family APGAR (ρ∈=∈0.26), PHQ-9 (ρ∈=∈-0.34), and mental health-related quality of life (ρ∈=∈0.40) but showed a lower correlation with physical health (ρ∈=∈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.