Teaching differential diagnosis to beginning clinical students.

Beginning clinical students cannot construct differential diagnoses the way more experienced students and physicians do because students lack knowledge and experience. Beginning students need a systematic framework for constructing a differential diagnosis. Such a framework can be developed using a two-dimensional grid, one axis being anatomic (referring to organs or structures), and the other listing types of disease (e.g., congenital, metabolic, infectious). Possible diagnoses that can explain major symptoms can then be fitted into the resulting grid. Examples are shown in this report for abdominal pain, chest pain, and edema. Such formulations may seem overly complete, but completeness is actually advantageous for students who are just starting to learn clinical medicine. Then, as they learn more about disease patterns and likelihood of occurrence, and elicit additional information from their patients, they can narrow and refine the diagnostic possibilities.