Strategy to achieve the best diagnosis

Getting the diagnosis correct when challenged by time, bias, and process makes all the difference in a patient’s outcome.


Jb Lee Photo

A necessary skill for dermatologists is understanding the cognitive processes involved in decision-making, its shortcomings, and seeing the potential for a missed or incorrect diagnosis. Friday’s session, Approach to Improving Diagnosis” (F011) spotlights effective practices and cognitive strategies to improve the diagnostic process.

“As physicians, we all strive to diagnose like the experts; that is, fast split-second diagnosis,” said session director Jason B. Lee, MD, FAAD, professor of the department of dermatology and cutaneous biology at Jefferson Medical College, director of Jefferson dermatopathology center and director of dermatopathology fellowship and pigmented lesion clinic. “The basis of this fast-thinking diagnosis are mental shortcuts or strategies referred to as heuristics. These mental strategies subconsciously focus on what we think are the most relevant aspects of a complex problem, providing a near instant solution to the problem.”

Take, for example, Dr. Lee said, “representativeness” and “availability heuristics.” While both serve to solve complex problems most of the time, they are subject to predictable, cognitive biases that can lead to errors in judgment. Such heuristics prevent an individual from being circumspect and lead to a tendency to ignore statistics or base rates of disease and focusing on what is familiar to the individual.

Confidence, Dr. Lee said, is a valued attribute in medicine that prevents circumspection and is another primary factor contributing to diagnostic errors. Those common and uncommon dermatologic diagnoses that are often missed in clinical settings, medical dermatology, hospital consultation, dermatopathology, teledermatology, and skin of color include tinea, psoriasis, and nummular dermatitis.

Uncommon diseases that are frequently missed are often associated with classically described characteristics, such as paraneoplastic pemphigus presenting with only lichenoid lesions rather than blisters. 

“A knowledge deficit contributes little to diagnostic errors,” Dr. Lee said. “This may be true in cognitive specialties of medicine, but it may have a significant role in perceptual specialties like ours.”

There are several strategies to improve the diagnostic process, according to Dr. Lee. Debiasing strategies or cognitive forcing strategies, for example, include being objective by framing the problem yourself, testing the hypothesis against the generated data, and taking a diagnostic time-out to consider other possible diagnoses.

“There are no studies, however, demonstrating that being aware of the cognitive processes and their pitfalls will improve the diagnostic process. In addition, how much impact we do have on cognitive processes that are subconscious is unknown,” Dr. Lee said. “What is important to know is that the accuracy of heuristics is based on experience, not some innate ability. Thus, experience in a regular setting with feedback is the best defense against diagnostic errors.”