Objective: This study examined the independent effect of a patient's weight on medical students' attitudes, beliefs and interpersonal behavior toward the patient, in addition to the clinical recommendations they make for her care.

Design: A total of 76 clinical-level medical students were randomly assigned to interact with a digital, virtual female patient who was visibly either obese or non-obese.

Methods: Interactions with the patient took place in an immersive virtual (virtual reality) clinical environment that allowed standardization of all patient behaviors and characteristics except for weight. Visual contact behavior was automatically recorded during the interaction. Afterward, participants filled out a battery of self-report questionnaires.

Results: Analyses revealed more negative stereotyping, less anticipated patient adherence, worse perceived health, more responsibility attributed for potentially weight-related presenting complaints and less visual contact directed toward the obese version of a virtual patient than the non-obese version of the patient. In contrast, there was no clear evidence of bias in clinical recommendations made for the patient's care.

Conclusion: Biases in attitudes, beliefs and interpersonal behavior have important implications because they can influence the tone of clinical encounters and rapport in the patient-provider relationship, which can have important downstream consequences. Gaining a clear understanding of the nature and source of weight bias in the clinical encounter is an important first step toward the development of strategies to address it.