Patient perspectives on how physicians communicate diagnostic uncertainty: An experimental vignette study.

Objective: We evaluated the effects of three different strategies for communicating diagnostic uncertainty on patient perceptions of physician competence and visit satisfaction.

Design/Setting: Experimental vignette-based study design involving pediatric cases presented to a convenience sample of parents living in a large US city.

Participants/Intervention(s): Three vignettes were developed, each describing one of three different ways physicians communicated diagnostic uncertainty to parents-(i) explicit expression of uncertainty ('not sure' about diagnosis), (ii) implicit expression of uncertainty using broad differential diagnoses and (iii) implicit expression of uncertainty using 'most likely' diagnoses. Participants were randomly assigned to one of the three vignettes and then answered a 37-item web-based questionnaire.

Main Outcome Measure(s): Outcome variables included parent-perceived technical competence of physician, trust and confidence, visit satisfaction and adherence to physician instructions. Differences between the three groups were compared using analysis of variance, followed by individual post hoc analyses with Bonferroni correction.

Results: Seventy-one participants completed the vignette questions. Demographic characteristics and scores on activation (parent activation measure [PAM]) and intolerance to uncertainty were similar across the three groups. Explicit expression of uncertainty was associated with lower perceived technical competence, less trust and confidence, and lower patient adherence as compared to the two groups with implicit communication. These latter two groups had comparable outcomes.

Conclusion: Parents may react less negatively in terms of perceived competence, physician confidence and trust, and intention to adhere when diagnostic uncertainty is communicated using implicit strategies, such as using broad differential diagnoses or most likely diagnoses. Evidence-based strategies to communicate diagnostic uncertainty to patients need further development.