Translating and Validating the Japanese Version of the Tolerance for Ambiguity Scale

Ambiguity is inherent in medicine, and tolerance for ambiguity (TFA) has recently been of substantial interest. Effective medical education for TFA requires a validated inventory; one validated measure in wide use is the seven-item TFA scale. In Japan, however, a tool for measuring TFA in undergraduate medical education has not been available. Here, we aimed to develop and validate the Japanese version of the TFA scale (J-TFA scale).

We translated the original English scale into Japanese following an international guideline. We then conducted a validation survey by distributing an online anonymous self-administered questionnaire to medical students at three medical schools in Japan. We assessed the structural validity and internal reliability of consistency of the scale.

A total of 399 participants were included in our analysis. We used a split-half validation approach, with exploratory factor analysis (EFA) on the first half and confirmatory factor analysis (CFA) on the second. EFA indicated a two-factor structure. CFA showed that the two-factor structure suggested by EFA had acceptable model fitness indices. Cronbach's alpha was 0.72, exceeding the satisfactory internal reliability consistency criteria.

The J-TFA scale was developed and its psychometric properties were confirmed. This instrument may be useful for future educational interventions and research on TFA.