First, a bit of terminology. In this curriculum we are using the term problem to denote any reason for which a patient seeks care, other than preventative reasons. “Problems” can be symptoms (“ my head hurts”), signs (“this bump on my face”), test results (“the people at the health fair said my blood pressure is too high”), or really anything that can be, medically speaking, concerning to the patient. The patient and their problem will be evaluated by a clinician and, in many cases, the problem will be diagnosed or definitively described in terms of an underlying condition. Conditions, in this curriculum, are used to denote the specific underlying disease or injury that is giving rise to the patient’s problem. Throat pain (problem) may be diagnosed as strep throat (condition), chest pain (problem) as coronary artery disease (condition) and so on. Sometimes patient’s problems are evaluated by clinicians and their assessment is merely a restatement of the problem; for example, an ER clinician evaluates a patient with abdominal pain and after a thorough evaluation, the patient’s assessment at discharge is still “abdominal pain.” It would also be correct to say that a patient was diagnosed with abdominal pain but note that in this case, the act of diagnosis does not contain any fundamental naming of the condition. In this case, “abdominal pain” as diagnosis, acts a kind of place holder indicating the problem for which the patient was evaluated but not committing to identifying an underlying condition. Clinicians will sometimes restate the problem as their final assessment if there isn’t sufficient evidence to warrant diagnosing a specific condition. Conditions, in this curriculum, are used to denote the specific underlying disease or injury that is giving rise to the patient’s problem.
Problem representation is not merely the passive description of the patient's signs and symptoms but the discursive act of adducing a range of possible underlying conditions that can be causing the problem. The first component of problem representation is identifying what kind of problem or thing you are dealing with. Patients may come in complaining of "feeling poorly." However, this complaint is conceptually murky. It is virtually impossible to adduce underlying problems working from the problem representation of "I am feeling poorly." The history provides the clinician with an opportunity to gather enough pertinent information about the patient's problem to locate the problem in a category. Categories of problems provide a framework for considering possible causes of the problem. Consequently, if the patient were to complain of "feeling poorly" the history would have to better define the problem so that it could be identified within a known category of clinical problems. When the patient says "I have been feeling poorly" the clinician may say something like "tell me about that." The patient may go on to describe how they have been feeling tired and having decreased energy for three weeks. Additionally, the patient reports running fever running around 101.9 to 102.3 using a temporal thermometer at home. "Feeling poorly" after a thorough history may be transformed into the category "subacute febrile illness with fatigue." As the problem representation begins to come into focus, the clinician will expand or modify the history to help better define the problem. With the problem "subacute febrile illness with fatigue," possible etiologies begin to emerge in the mind of the clinician – infection, malignancy and rheumatologic disorders. Consequently, the clinician adds questions about associated signs and symptoms like cough, weight loss, new skin lesions as well as recent travel, household contacts, possible tick exposure and possible occupational exposures.
Satisfied that the patient's problem has been adequately represented by the history, the clinician will perform a physical examination to better define the problem.
The next component in problem representation is identifying the problem within a known category of conditions. The category of subacute febrile illness with fatigue is sufficiently well defined to create a differential diagnosis; mononucleosis, lymphoma and Lyme disease come to mind (non-exhaustive list).