Conceptual knowledge and decision strategies in relation to hypercholesterolemia and coronary heart disease

This paper reports on a study that examines physicians' understanding of co ncepts and decision making in problems pertaining to hypercholesterolemia a nd coronary heart disease (CHD). The study was carried out in two phases: ( 1) a simulated clinical interview in which two clinical problems were prese nted and (2) a session in which subjects responded to a series of questions . The questions were related to the analysis of risk factors, diagnostic cr iteria (DC) for determining elevated lipid values, and differential diagnos is for lipid disorders. The subjects included 12 family practitioners who w ere randomly selected from a continuing medical education program at McGill University. The results indicate that all subjects exhibited gaps in their understanding of domain concepts. In particular, most physicians demonstra ted a lack of knowledge concerning the primary genetic disorders that contr ibute to CHD, as well as deficiencies in understanding the secondary causes of hypercholesterolemia. The majority of subjects tended to overestimate t he lipid value intervals for determining patients at high risk. Physicians had no difficulty diagnosing the first patient problem of familial hypercho lesterolemia, but failed to identify the problem of elevated lipids seconda ry to hypothyroidism. We observed a dissociation between subjects' conceptu al understanding and their application of knowledge in solving patient prob lems. The implications of this work are discussed in terms of the cognitive dimensions of technologies for supporting learning and evidence-based deci sion making. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.