Harvard med prof. explains doctors’ mistakes

Tuesday, October 7, 2008

Medical mistakes go beyond operating on the wrong limb or administering an incorrect dosage of a drug, Jerome Groopman said Tuesday in MacMillan 117. Groopman, a professor at Harvard Medical School, said he’s interested in the medical mistakes that don’t make headlines, and which he said are far more frequent­ – misdiagnoses.

Groopman, also the chief of experimental medicine at the Beth Israel Deaconess Medical Center and a staff writer on medicine for the New Yorker, was the keynote speaker for the Harriet W. Sheridan Literature and Medicine Lecture. Groopman was supposed to speak last spring but a personal injury forced him to reschedule. Speaking from a seat on a stage, he said the lecture would be more like a “fireside chat.”

MacMillan 117 was packed with a variety of community members as well as undergraduate students, students in the Program in Liberal Medical Education and medical students­.

Groopman spoke about the ways that doctors form their medical diagnoses, which is also the subject of his recently published book, “How Doctors Think.”

Doctors think like magnets, he said; they gather a wide range of information and draw conclusions quickly. “The average doctor interrupts a patient within the first 18 seconds of asking them what’s wrong,” Groopman said.

Doctors’ diagnoses are correct 80 to 85 percent of the time, Groopman said. For a stock broker or baseball player, such a rate of accuracy would be considered a success. For doctors, however, he said being wrong 15 to 20 percent of the time is “very high.”

“The delay in diagnosis or the failure to make a real diagnosis leads to real harm to the patients” in half those cases, Groopman said.

Groopman said he researched cognitive psychology and experimental psychology in search of ways to improve this percentage. In his research, he developed a theory of three cognitive biases that affect the ways in which doctors diagnose patients.

These “thinking traps” are what he called the three A’s: anchoring, availability and attribution. Anchoring occurs when doctors fixate on the first piece of information they receive, even if it’s not the most important. Availability occurs when doctors diagnose patients according to what they have recently seen in other patients, or simply thought about. Attribution, the last bias, occurs when doctors rely on social stereotypes to make diagnoses. For example, it can be tempting to diagnose a Marine with a swollen liver as an alcoholic, even if it’s not the case, Groopman said.

He also said he hoped that cognitive science would be taken seriously by physicians and educators.

While Groopman said that doctors must take time to reflect on the way they are drawing conclusions, he also noted, in response to a question, that part of the problem lies within the design of the current medical system. “People are not being paid to think well,” he said. The current system rewards taking action and does not incentivize doctors to take time to think about preventative measures, he said.

After the lecture, students and community members reconvened in a tent outside MacMillan for a book signing and refreshments.

“I thought he was phenomenal,” Nitin Aggarwal MD’11 said. “It was good to hear so we can keep in mind what to know when we’re training to be physicians.”

Kevin Liou ’10 was especially interested in the new ways of thinking Groopman encouraged. “He teaches us to think outside of the box, to take into consideration those other factors that affect our thinking,” Liou said. “I just feel like medicine needs to expand its perspective.”

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