Objective  To develop an Occupational Strain Scale for Chinese employees and to evaluate its reliability and validity.

  Methods  An initial scale was developed based on literature reviews, semi-structured interviews, Delphi expert consultation and a pilot survey. Then the complied scale was self-administered online among 2 432 in-service employees sampled at 10 domestic enterprises and institutions in 5 cities of Sichuan province during March 2019. Valid information were collected from 2 191 responders; of them, 1 096 were assessed for exploratory factor analysis and other process for item screening and 1 095 were assessed for the scale's reliability and validity analysis. Confirmatory factor analysis was adopted in validity test and Cronbach'α and split-half reliability were used in reliability evaluation.

  Results  The established scale included 15 items for cognitive behavioral, psychological and physical strain, which could explain 68.796% of total variance of the scale. The results of confirmatory factors analysis demonstrated that the three-domain model fitted well (χ²/df = 3.894, normed fit index = 0.969, comparative fit index = 0.977, incremental fit index = 0.977, Tucker-Lewis index = 0.971, root mean square error of approximation = 0.051). The Cronbach α coefficient was 0.935 for the general scale and ranged 0.789 – 0.923 for the 3 subscales. The split-half reliability coefficient was 0.863 for the general scale, and ranged 0.766 – 0.898 for the 3 subscales.

  Conclusion  The developed Occupational Strain Scale is of good reliability and validity and could be applied for measurement of occupational strain in Chinese working populations.