Structure of medical explanation: a semantic model

There is a body of evidence revealing that poor outcomes, complaints and malpractice litigation are due, in part, to poor communication and absence of satisfactory explanation. We view explanation as a linguistic structure that should promote understanding but there is no agreement on what such a structure should be. We propose a semantic model for thinking about explanation to patients in a more robust way. We constructed our model by thematically analyzing the explanations provided by 21 senior residents in medicine. Using a standardized case of endocarditis, we asked the residents to explain the problem as if they were addressing a patient. We recorded and transcribed their explanations, systematically identifying and analyzing themes and patterns. Our analysis focused on how the residents used evidence, articulated reasons and causes, employed deduction and inference, and made analogies and generalizations. We propose a theoretical model of explanation based on two types of relations: vertical relations of correspondence C between the language of the patient and the medical language and horizontal causal relations R made explicit. This model is inspired by works in philosophy of science that have described explanations as instances that can be subsumed under a general pattern or law. ¹ The model could be used as a theoretical framework to test if it improves how patients understand medical explanations provided by physicians. We suggest that medical curriculum should include attention to processes of explanation with the express goal advancing patient understanding, and to counter suggestions that the problem with explanation is that patients don’t understand.