Editor's note: This popular story from the Daily Briefing's archives was republished on Dec. 5, 2018.
Amid the push to make medical recommendations more evidence-backed and statistically robust, medical journals have shifted away from publishing anecdotal, open-ended accounts of individual patients—and we've lost something important in the process, Siddhartha Mukherjee writes for New York Times Magazine.
The woman who saw dragons
"The tradition of writing case reports was carried forward for centuries," Mukherjee writes. Unlike today's traditional randomized studies, case studies relied largely on anecdotes, observation, and description, and they did not always draw medical conclusions.
For example, Mukherjee recalls a case study published in The Lancet in 2011 that "hooked" him. The case involved a 52-year-old woman who came to an outpatient clinic with a "lifelong history of seeing people's faces change into dragonlike faces."
The woman, the case study stated, "could perceive and recognize actual faces, but after several minutes, they turned black, grew long, pointy ears and a protruding snout and displayed a reptiloid skin and huge eyes in bright yellow, green, blue, or red. ... She saw similar dragonlike faces drifting toward her many times a day from the walls, electrical sockets, or the computer screen."
The doctors in the study gave the woman a full neurological exam and reviewed her medical history, which revealed she had a history of hallucinations and was "'born with a caul'"—"a condition in which the amniotic sac covers the baby at birth, creating a veil of tissue across the face," Mukherjee writes.
The woman ultimately was prescribed an anti-epileptic pill and a pill for Parkinson's disease, which diminished her hallucinations, Mukherjee writes. But the case study authors offered no diagnosis Mukherjee writes, "only description, observations without explanations."
How case studies have changed
In recent years, those "[a]necdotal, observational and descriptive ... case studies" have been cast aside in favor of explanatory and statistical studies, Mukherjee writes.
He notes that observational studies are largely seen as useless today if they don't "help explain some principle of physiology, or [are] somehow incorporated into an objective (preferably randomized) trial." Instead of being open-ended, case studies became neatly tied up with a diagnosis of some kind, and those observational case studies have been viewed as little more than "medical 'trivia'" or "just-so stories that might entertain but could not teach."
The case for case studies
In doing away with these open-ended case studies, Mukherjee argues, the medical field is losing something important. "I miss the textural idiosyncrasies of suffering that can be found only in real testimony," he writes, adding that that he's worried the "unknown unknowns will go unwritten—that buried within such cases, there might have been a cosmos of inexplicable observations that might, in turn, have inspired new ways of thinking about human pathology."
Mukherjee writes that he hopes these types of case studies will make a comeback. "[P]erhaps we might revive the case study that looks to the future: I cannot diagnose this condition, or explain it away, but I will record it in its fullest, richest form for another generation of medical students to puzzle over," he writes (Mukherjee, New York Times Magazine, 7/17).
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- Evidence-based practice (EBP)
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