Abstract
BACKGROUND: The Medical Staff Occupational Stress Scale (MSOSS) is a timely tool for the measurement of occupational stress among medical staff. It included a childhood stress dimension and seven other work-related stress dimensions. This study aimed to evaluate the psychometric properties and measurement invariance of the MSOSS using a large cohort of clinical nurses from Southeast China. METHOD: A province-level survey was conducted from January 1st 2022 to May 31st 2022. Full-time clinical nurses from multiple hospitals in Hainan province were recruited. A total of 2989 nurses (1639 from secondary hospitals and 1350 from tertiary hospitals) completed the survey. The reliability of the MSOSS was assessed by its internal consistency. The validity of the MSOSS was assessed by its structural validity, convergent validity and concurrent validity. A series of multi-group confirmatory factor analyses were conducted to test and establish measurement invariance across variables such as age, work duration, hospital level, and job title. RESULTS: The MSOSS exhibited excellent internal consistency in the different cohorts (Cronbach's α = 0.954-0.965, omega coefficient = 0.956-0.967 and Spearman-Brown coefficient = 0.883-0.905). The MSOSS exhibited stable structural validity and the confirmative factor analysis showed that the comparative fit index (CFI), incremental fit index (IFI) and Tucker-Lewis Index (TLI) were all around 0.9 in the different cohorts, indicating a good model fit. The measurement invariance of the MSOSS across hospital level, age, work duration and job title was supported by its metric invariance, scalar invariance and residual invariance. Cut-offs for the MSOSS as a depression and anxiety screening tool were also calculated. Scores above 102 and 207 were found to be indicative of depression and anxiety, respectively. CONCLUSIONS: The MSOSS proved to be a suitable tool for assessing occupational stress among clinical nurses.