<?xml version='1.0' encoding='UTF-8'?><xml><records><record><source-app name="HighWire" version="7.x">Drupal-HighWire</source-app><ref-type name="Journal Article">17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cai, Xinyan</style></author><author><style face="normal" font="default" size="100%">Ebell, Mark H.</style></author><author><style face="normal" font="default" size="100%">Russo, Garth</style></author></authors><secondary-authors></secondary-authors></contributors><titles><title><style face="normal" font="default" size="100%">A Quantitative Study of the Decision Threshold for the Diagnosis of Infectious Mononucleosis</style></title><secondary-title><style face="normal" font="default" size="100%">The Journal of the American Board of Family
                Medicine</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2022</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2022-12-23 00:00:00</style></date></pub-dates></dates><pages><style  face="normal" font="default" size="100%">1065-1071</style></pages><doi><style  face="normal" font="default" size="100%">10.3122/jabfm.2022.210185R1</style></doi><volume><style face="normal" font="default" size="100%">35</style></volume><issue><style face="normal" font="default" size="100%">6</style></issue><abstract><style  face="normal" font="default" size="100%">Background: Ordering a serologic test for infectious mononucleosis (IM) in all young patients with sore throat is costly and impractical. The test threshold to determine when to order a diagnostic test for IM based on the patient’s symptoms has not been previously studied.Objective: To determine the test threshold for IM in the management of patients with sore throat.Design and Setting: Online surveys were sent to a convenience sample of US primary care clinicians regarding their decision making about whether or not to order a test for IM in a patient with sore throat.Method: 7 clinical vignettes were created, each with a different combinations of symptoms and signs. The probability of IM for each vignette was estimated by the investigator based on the number of symptoms present to generate a plausible range of disease probabilities. Clinicians were then asked to decide whether to test or not test for IM, and mixed-effect logistic regression was used to determine the test threshold for IM where half of physicians chose to test and half chose not to test.Results: A total of 117 clinicians provided responses for a total of 819 clinical vignettes. The overall test threshold for IM as estimated using the logistic regression was 9.5% (95% CI: 8.2% to 10.9%). The test threshold for clinicians practicing greater than 10 years was significantly higher than for those practicing less or equal to 10 years (10.5% vs 7.3%, P = .02). No significant differences between specialties and practice sites were found with respect to the test threshold.Conclusion: This study identified a test threshold for IM of approximately 10% based on realistic clinical vignettes. This threshold was stable regarding the clinician’s specialty and practice sites and could be used in the development of a clinical prediction rule to determine the cutoff for low- versus high-risk groups.</style></abstract></record></records></xml>