To a medical student who requires 2 hours to collect a patient's history and perform a physical examination and several additional hours to organize that information into a coherent presentation, an experienced clinician's ability to decide on a diagnosis and management plan in a fraction of the time seems extraordinary. What separates the experienced clinician's performance from that of the novice is an elusive quality called "expertise." The first part of this chapter will provide a brief introduction to what is known about the development of expertise in clinical reasoning.
Equally bewildering to the student are the proper use of diagnostic tests and the integration of the results into the patient's clinical assessment. A novice medical practitioner typically uses a "shotgun" approach to testing, hoping to hit a target without knowing exactly what that target is. The expert, in contrast, usually has a specific target in mind and adjusts the testing strategy to it. The second part of the chapter will review briefly some of the crucial basic statistical concepts useful in the interpretation of diagnostic tests. Quantitative tools available to assist in clinical decision-making also will be discussed.
Evidence-based medicine (EBM) is the term used to describe the integration of the best available research evidence with clinical judgment and experience as applied to the care of individual patients. The third part of the chapter will provide a brief overview of some of the tools of EBM.
Brief Introduction to Clinical Reasoning
It is surprisingly difficult to define clearly what is meant by "clinical expertise." Chess has its masters, music its virtuoso performers, and athletics its Olympians. But in medicine, once training is complete and the boards are passed, there are no further tests or benchmarks of performance or ability that can be used to identify those who have attained the highest level of abilities in their clinical roles. Of course, there are always a few clinicians who are believed by their colleagues to have special problem-solving abilities: the "elite" who are consulted when particularly difficult or obscure cases have baffled everyone else. But for all their expertise, such doctors typically cannot explain what processes and methods they use to achieve their impressive results. Furthermore, it is not clear that their diagnostic virtuosity can be generalized. In other words, an expert on hypertrophic cardiomyopathy may be no better (and possibly worse) than a first-year resident at diagnosing and managing a patient with neutropenia, fever, and hypotension.
Broadly construed, clinical expertise includes not only cognitive dimensions and the integration of verbal and visual cues or information but also complex motor skills that are required in the performance of various invasive and noninvasive procedures and tests. In addition, the ability to communicate effectively with patients and work effectively with members of the medical team could be included as important aspects of "the complete package" of expertise in ...