Jennifer N Stojan1, Michelle Daniel, Helen K Morgan, Laurie Whitman, Larry D Gruppen. 1. J.N. Stojan is assistant professor, Departments of Internal Medicine and Pediatrics, University of Michigan Medical School, Ann Arbor, Michigan. M. Daniel is assistant dean for curriculum and assistant professor, Departments of Emergency Medicine and Learning Health Sciences, University of Michigan Medical School, Ann Arbor, Michigan; ORCID: http://orcid.org/0000-0001-8961-7119. H.K. Morgan is clinical assistant professor, Departments of Obstetrics and Gynecology and Learning Health Sciences, University of Michigan Medical School, Ann Arbor, Michigan. L. Whitman is program manager, Standardized Patient Program, and standardized patient educator, University of Michigan Medical School, Ann Arbor, Michigan. L.D. Gruppen is professor, Department of Learning Health Sciences, and director, University of Michigan Master of Health Professions Education Program, Ann Arbor, Michigan; ORCID: http://orcid.org/0000-0002-2107-0126.
Abstract
PURPOSE: Learning to make decisions under uncertain conditions is a critical component of diagnostic and therapeutic reasoning. This study sought to determine treatment decisions medical students make when presented with different thresholds of diagnostic uncertainty and whether they appropriately adjust diagnostic probabilities with test information. METHOD: Two classes (2015, 2016) of fourth-year students (N = 342) were presented a patient with viral pneumonia and given 10%, 20%, or 50% pretest probabilities of that patient having a superimposed bacterial infection. Students decided to not treat, order a diagnostic test to guide management, or treat without testing based on these probabilities. The 2015 class was provided a posttest probability of 10% or 50% and asked to adjust their initial treatment decision. RESULTS: When given a low (10%) pretest probability, students were less likely to decide to treat (6%) and more likely to decide not to treat (36%). The percentage of students deciding to treat increased as the pretest probability of a superimposed infection increased from 10% to 50%, while the percentage of students not wanting to treat decreased. Interestingly, at 10%, 20%, and 50% pretest probability levels, most students were unable to decide and chose to order another test (57%, 67%, and 64%, respectively). When provided low and high posttest probabilities, students appropriately adjusted their decision making, but 29% to 32% still wanted additional testing. CONCLUSIONS: Students adjusted treatment decisions to reflect different levels of diagnostic uncertainty, but varied considerably in their individual thresholds to make decisions, possibly contributing to unnecessary testing.
PURPOSE: Learning to make decisions under uncertain conditions is a critical component of diagnostic and therapeutic reasoning. This study sought to determine treatment decisions medical students make when presented with different thresholds of diagnostic uncertainty and whether they appropriately adjust diagnostic probabilities with test information. METHOD: Two classes (2015, 2016) of fourth-year students (N = 342) were presented a patient with viral pneumonia and given 10%, 20%, or 50% pretest probabilities of that patient having a superimposed bacterial infection. Students decided to not treat, order a diagnostic test to guide management, or treat without testing based on these probabilities. The 2015 class was provided a posttest probability of 10% or 50% and asked to adjust their initial treatment decision. RESULTS: When given a low (10%) pretest probability, students were less likely to decide to treat (6%) and more likely to decide not to treat (36%). The percentage of students deciding to treat increased as the pretest probability of a superimposed infection increased from 10% to 50%, while the percentage of students not wanting to treat decreased. Interestingly, at 10%, 20%, and 50% pretest probability levels, most students were unable to decide and chose to order another test (57%, 67%, and 64%, respectively). When provided low and high posttest probabilities, students appropriately adjusted their decision making, but 29% to 32% still wanted additional testing. CONCLUSIONS: Students adjusted treatment decisions to reflect different levels of diagnostic uncertainty, but varied considerably in their individual thresholds to make decisions, possibly contributing to unnecessary testing.
Authors: Geoffrey K Spurling; Peter R Mansfield; Brett D Montgomery; Joel Lexchin; Jenny Doust; Noordin Othman; Agnes I Vitry Journal: PLoS Med Date: 2010-10-19 Impact factor: 11.069