The Chinese version of Defensive Medicine Scale (DMS): reliability and validity test among physicians

Physicians are inclined to resort to defensive medicine (DM) for self-protection due to the increasing potential risk of medical litigation. DM is globally prevalent and has become an impediment to the development of healthcare. However, there is a lack of validated tools specifically designed to assess DM in China. Therefore, this study aimed to evaluate the psychometric properties of the Chinese version of Defensive Medicine Scale (DMS) among clinicians to provide a practicable tool for relevant research.

The present research consists of two phases. In Phase 1, DMS was administered to survey 327 physicians, and the collected data were obtained for item analysis and exploratory factor analysis. Phase 2 applied DMS to survey 323 physicians, from which the data was used for confirmatory factor analysis, and reliability and cross-cohort consistency tests. Moreover, the participants of Phase 2 were required to complete Workplace Well-Being Scale (WWBS), Career Commitment Scale (CCS), Occupational Disidentification Scale (ODS), Intent to Leave Scale (ILS), and Difficult Doctor-Patient Relationship Questionnaire (DDPRQ-10) to test the convergent validity of DMS.

The Chinese version of DMS consists of 10 items divided into 2 dimensions, Positive Defensive Medicine (PDM) and Negative Defensive Medicine (NDM). The confirmatory factor analysis showed that the two-factor model fitted well (χ²/df = 2.540, RMSEA = 0.069, CFI = 0.981, IFI = 0.981, TLI = 0.971, PNFI = 0.646, PCFI = 0.654, SRMR = 0.044). Furthermore, the total score and the score of each dimension for DMS had a significant negative correlation with WWBS and CCS scores, and a significant positive correlation with ODS, ILS, and DDPRQ-10 scores. The Cronbach's α coefficients for the total DMS and PDM and NDM dimensions were 0.917, 0.935, and 0.842, respectively; the split-half reliability coefficients were 0.922, 0.947, and 0.839, respectively. In addition, DMS showed cross-gender invariance.

The Chinese version of DMS has been demonstrated to be an effective tool to assess defensive medicine among Chinese physicians with good psychometric properties.