Psychometric validation of the Perceived Stress Scale (PSS-10) among family caregivers of people with schizophrenia in China

BACKGROUND: The 10-item Perceived Stress Scale (PSS-10) is a widely used measure of perceived stress that has been validated in various populations, yet with inconsistent results on its factor structure. The present study examines the reliability and validity of the PSS-10 in a population not previously examined: Chinese family caregivers of persons with schizophrenia, with a focus on factor analysis. METHODS: A sample of 449 family caregivers of persons with schizophrenia was recruited for psychometric testing of the scale. The factor structure of PSS-10 was tested by randomly dividing the sample into two groups for both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The scale was further tested for internal consistency, test–retest reliability, convergent validity, discriminant validity and concurrent validity. RESULTS: EFA extracted two factors: perceived helplessness with six negative phrasing items and perceived efficacy with four positive phrasing items. CFA confirmed the structure of two factors with satisfactory model fit indices. Convergent validity was supported by high standard regression weight (0.78–0.92), average variance extracted (AVE=0.79–0.81) and composite reliability (0.88–0.94), while discriminant validity was confirmed by higher AVE estimates than the squared interconstruct correlations. The PSS-10 showed good internal consistency and test–retest reliability, with Cronbach’s alpha of 0.79 and intraclass correlation coefficient of 0.91, respectively. Concurrent validity was demonstrated by its significant positive correlations with stigma, depression and anxiety, as well as significant negative correlations with social support, family functioning and positive caregiving experiences. CONCLUSION: The two-factor PSS-10 has good psychometric characteristics assessing the perceived stress of family caregivers of people with schizophrenia. The findings indicate that the PSS-10 can be used to measure perceived stress in future research and practice among caregivers of people with schizophrenia, and potentially, other caregiving samples.