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The Inability to Calculate Predictive Values: an Old Problem that Has Not Gone Away
1Department of Family Medicine and Community Health, University of Minnesota Medical School, 420 Delaware St. SE, MMC 381, Minneapolis, MN 55455 USA.
Background:
Previous studies suggest that many physicians and medical trainees have trouble calculating the probability that a patient has a condition, also known as the predictive value.
Activity:
Two questions from the medical literature were administered to medical students, residents (post-medical school), fellows (post-residency), and faculty physicians.
Results:
Only 6% answered both questions correctly. Most commonly, the participants grossly overestimated the probability of disease.
Discussion:
Physicians still struggle with the ability to calculate predictive values, a skill that affects all branches of medicine and will become more consequential as new tests are administered to patients at low risk for disease.
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