During the first 2 years of medical school we study basic sciences. We learn biochemistry, physiology, histology, anatomy, pharmacology and microbiology. Jerome Kassirer, in a wonderful Academic Medicine essay,
These concepts foster the teaching and learning of the diagnostic process, the complex trade-offs between the benefits and risks of diagnostic tests and treatments, and cognitive errors in clinical reasoning. The teaching of clinical reasoning need not and should not be delayed until students gain a full understanding of anatomy and pathophysiology. Concepts such as hypothesis generation, pattern recognition, context formulation, diagnostic test interpretation, differential diagnosis, and diagnostic verification provide both the language and the methods of clinical problem solving. Expertise is attainable even though the precise mechanisms of achieving it are not known.
The master diagnostician must excel in clinical reasoning. We all have seen expert diagnosticians who "just know" how to avoid the pitfalls of diagnosis.
The master diagnostician knows when System 1 (intuitive or fast) thinking suffices. They know this because their experience has taught them a refined illness script. For example, an infiltrate on CXR and a cough is not enough to diagnose CAP. They expect a specific time course of symptoms and a response to antibiotics. When something does not fit, they know to slow down.
The study of expertise in medical education has tended to follow a tradition of trying to describe the analytic processes and/or nonanalytic resources that experts acquire with experience. However, the authors argue that a critical function of expertise is the judgment required to coordinate these resources, using efficient nonanalytic processes for many tasks, but transitioning to more effortful analytic processing when necessary. Attempts to appreciate the nature of this transition, when it happens, and how it happens, can be informed by the evaluation of other literatures that are addressing these and related problems. The authors review the literatures on educational expertise, attention and effort, situational awareness, and human factors to examine the conceptual frameworks of expertise arising from these domains and the research methodologies that inform their practice. The authors propose a new model of expert judgment that we describe as a process of slowing down when you should.
Slowing down refers to switching from fast mode to slow mode also known as analytic reasoning. Our experts know when one must ponder and search the literature. They know when the presentation suggests that the diagnosis is not straightforward.
We who aspire to become master diagnosticians may benefit from studying the basic science of clinical reasoning. We have no randomized controlled trials to show that such study makes a difference, so I cannot make a firm recommendation. But my intuitive feeling tells me that the more we understand the science of reasoning.
Now all the reasoning in the world will not help if the data are not collected properly and interpreted properly. The best diagnosticians must take their own histories and do their own physical exams.
Given that caveat, I believe that studying the basic science of cognition helps many diagnosticians. The Journal of General Internal Medicine features a clinical problem solving presentation every 3 months. My colleagues and I contribute 2 presentations each year. These CPS presentations have the unique feature of including a discussion of the cognitive process. The American Journal of Medical Science is starting a similar feature.
