Validation of the professional identity questionnaire among medical students

BACKGROUND: Professionalism represents a cornerstone of the medical profession, prompting medical educators to actively develop instruments to measure professional identity formation among medical students. A quantitative approach to this problem has been lacking. Hence in this study, we investigate the validity and reliability of using Brown et al.’s [1986] Professional Identity Questionnaire (PIQ) to measure professional identity among medical students. METHODS: We used the American Psychological Association’s account of validity and reliability to examine the PIQ in terms of its internal structure, its relation to a validated motivation scale, its content, and its internal consistency. To this end, we performed two factor analyses, a Pearson’s correlation test, an expert evaluation and measured Cronbach’s alpha, respectively.. RESULTS: Factor analysis revealed two latent factors underlying the items of the PIQ. We found a negative to positive spectrum of Pearson’s correlations corresponding to increasingly internal qualities of motivation. Experts unanimously rated four out of ten of the PIQ’s items as relevant, reliability analysis yielded a Cronbach’s alpha value of 0.82. CONCLUSION: Despite poor ratings by experts in the field, these results illustrate the PIQ as a valid and reliable quantitative measure of medical students’ professional identity; its two factors reflecting the measure of attached and detached attitudes towards the medical profession. Educators may use the instrument as a tool for monitoring PIF among their students, as well as for designing and evaluating their medical curriculum. Future research might build on the current findings by investigating other dimensions of the PIQ’s validity, including response process validity, predictive validity and consequential validity. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12909-021-02704-w.