BACKGROUND: Individual-centred career questionnaires are important for understanding the motivations of medical students. This study aimed to collect validity evidence of a questionnaire to measure the career choice of medical undergraduates. METHODS: A cross-sectional survey was sent to third-year undergraduate students at a Chinese university-affiliated hospital. The questionnaire was formed using items that were selected after a systematic literature review. Item reduction was conducted using Mokken scale analysis, followed by reliability and validity testing, which described the validity evidence of the content, response process and internal structure. RESULTS: The preliminary 20-item questionnaire was returned by 213 undergraduate students (response rate: 86.59%). To construct a monotone homogeneity model, 6 items were removed after testing for unidimensionality, local independence, and latent monotonicity according to the sequence. The final questionnaire included 14 items in two subscales: a 10-item ‘career advantage’ subscale and a 4-item ‘career disadvantage’ subscale. The questionnaire was judged to be acceptably reliable (Molenaar-Sijtsma method: 0.87 and 0.75, Cronbach’s alpha: 0.87 and 0.74) and to have good construct validity (χ2/df: 1.748, normed fit index: > 0.9, comparative fit index: > 0.9, root mean square error of approximation: 0.05–0.08). Male and female undergraduates had different responses regarding their salary, subspecialty, career prospects, and ability to serve their relatives. Male undergraduates might be more willing to accept on-call positions and have subspecialties with greater likelihoods of patient–physician conflict. CONCLUSION: We used Mokken scale analysis to develop and collect evidence of the validity of a 14-item questionnaire regarding career preferences among Chinese medical undergraduate students. This short and simple questionnaire may provide a suitable tool for exploring insights regarding the motivations of Chinese medical students. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12909-022-03340-8.
Development of a career questionnaire for medical undergraduates using Mokken scale analysis