The undue influence of genetic information on medical students’ treatment decisions

Abstract

Introduction: Knowledge of the genetic basis of health conditions can influence how the public perceives their own and others health. When there are known genetic associations for such conditions, genetic essentialist biases facilitate deterministic thinking and an over emphasis of genetic causality. This study investigates the role that genetic essentialist biases play in medical decision making. Methods: Third and fourth year medical students (N = 102) read a scenario in which a patient presents with gastroenterological symptoms. Half of the students were told that the patient tested positive for HLADQ2 a gene implicated in, but not deterministic of, coeliac disease. The other half received no genetic information. Students were assessed on their recommendations for investigation and management using a multiple-choice questionnaire. Twenty-two of these students participated in a qualitative follow up which used semi-structured interviews to explore the reasoning behind students responses. Results: Management recommendations differed between the two groups, with those receiving genetic information more likely to recommend a gluten free diet. Recommendations for further investigation did not differ significantly between groups. Interviews suggested that these findings arose despite the students good understanding of the common non-deterministic nature of genes, such as HLADQ2. Differences in management recommendations suggest that the inclusion of genetic information unduly biased students towards a premature diagnosis of a serious health condition coeliac disease. Follow-up interviews introduce the possibility that observed manipulation-based differences may have been based on anticipated expectations of examiners. Thus, research in clinical settings is needed to ascertain whether genetic essentialist biases are implicitly influencing medical students under examination conditions or whether they react to the assumptive genetic biases of examiners. Conclusion: The present findings indicate that genetic essentialist biases may affect clinical decision making of senior medical students. While the findings may also arise as an artifact of a conscious exam-taking strategy, there are substantial arguments against this interpretation.