Psychometric properties of the critical thinking disposition assessment test amongst medical students in China: a cross-sectional study

BACKGROUND: Critical thinking disposition helps medical students and professionals overcome the effects of personal values and beliefs when exercising clinical judgment. The lack of effective instruments to measure critical thinking disposition in medical students has become an obstacle for training and evaluating students in undergraduate programs in China. The aim of this study was to evaluate the psychometric properties of the CTDA test. METHODS: A total of 278 students participated in this study and responded to the CTDA test. Cronbach’s α coefficient, internal consistency, test-retest reliability, floor effects and ceiling effects were measured to assess the reliability of the questionnaire. Construct validity of the pre-specified three-domain structure of the CTDA was evaluated by explanatory factor analysis (EFA) and confirmatory factor analysis (CFA). The convergent validity and discriminant validity were also analyzed. RESULTS: Cronbach’s alpha coefficient for the entire questionnaire was calculated to be 0.92, all of the domains showed acceptable internal consistency (0.81–0.86), and the test-retest reliability indicated acceptable intra-class correlation coefficients (ICCs) (0.93, p < 0.01). The EFA and the CFA demonstrated that the three-domain model fitted the data adequately. The test showed satisfactory convergent and discriminant validity. CONCLUSIONS: The CTDA is a reliable and valid questionnaire to evaluate the disposition of medical students towards critical thinking in China and can reasonably be applied in critical thinking programs and medical education research.