Implicit and Explicit Bias Toward Substance Use: A Cross-Sectional Study Comparing Health Care Professionals, Trainees, and the Public

Background: Health care professionals (HCPs) are known to exhibit explicit and implicit biases toward individuals who use substances. However, it remains unclear whether these biases differ from those of the general population and, if so, when such differences emerge along the training continuum. This study examined whether implicit and explicit biases vary between the general population, health care learners (HCLs), and HCPs, and whether training and experience may modulate the congruence between these bias types. Methods: Participants included HCPs, HCLs, and members of the general populations recruited via crowdsourcing. All completed explicit bias instruments and an Implicit Association Test (IAT). Explicit bias scores underwent principal components analysis yielding 2 components: Prejudice (environmental biases) and Stigma Endorsement (personal negative attitudes). Component scores were compared across groups using one-way ANOVA. Fisher’s r -to- z transformations compared correlation coefficients between the 3 groups. Hierarchical multiple regression then examined explicit-implicit bias congruence while controlling for key covariates and profession, namely, medicine, nursing, paramedicine (ie, Emergency Medical Technicians, paramedics, and related roles). Results: The sample elicited moderate-to-strong negative biases overall. Groups did not significantly differ in explicit or implicit biases. However, HCPs exhibited significantly stronger correspondence between IAT and Prejudice scores ( r = .38, P < .001) than HCLs ( r = .10, P = .35) and the general population ( r = .08, P = .23); the latter 2 groups did not significantly differ. This difference was maintained in the regression model controlling for key covariates. Conclusions: Although implicit and explicit bias toward individuals who use substances did not differ across HCP, HCL, and the general population, HCPs demonstrated significantly greater alignment of implicit and explicit bias scores. These findings suggest that training and professional experience may not be sufficient to reduce stigma toward this group. In fact, greater experience and environmental biases may be cyclically reinforced.