Validation of the professional identity formation - developing acale among Vietnamese medical students: a psychometric analysis

Professional identity formation (PIF) is a crucial developmental process in medical education, involving the integration of core values, knowledge, and skills necessary for becoming competent and ethical physicians. The professional identity formation - developing scale (PIF-DS) is a quantitative, self-administered questionnaire to assess the degree of identity maturation and professional socialization. Originally developed in Japan, its applicability in research sites from other cultural settings, as in Vietnam, requires validation. This study aimed to validate the PIF-DS among 305 sixth year medical students (MS-Y6) from the University of Medicine and Pharmacy at Ho Chi Minh City (UMP-HCMC). A multi-phase mixed-method design was adopted, following guidelines for instrument validation. The validation included: 1) content validity assessment; 2) construct validity via exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), and 3) internal consistency analysis. After the content validation phase, the translated instruments were enhanced both in concepts and semantic equivalency. Consequently, EFA identified a five-factor structure: self-control as a professional, awareness of being a doctor, reflection practice, execution of social responsibility, and internal-external self-harmonization. CFA supported a revised model excluding item 9, showing good fit (comparative fit index [CFI]=0.92, Tucker-Lewis Index [TLI]=0.89, root mean square error of approximation [RMSEA] robust=0.086, standardized root mean square residual [SRMR]=0.056). Internal consistency was robust across all factors, with Cronbach’s alpha ranging from 0.76 to 0.81. These findings provide preliminary evidence for the validity and reliability of the PIF-DS in assessing PIF among MS-Y6 at UMP-HCMC. The Vietnamese version of the PIF-DS demonstrates strong psychometric properties and cultural relevance for assessing professional identity among MS-Y6. Its application can support curriculum evaluation and guide interventions to foster ethical, social responsible physicians in Vietnam.