Diagnostic certainty for acute otitis media.

Our primary objective was to assess diagnostic accuracy for acute otitis media (AOM) relative to the criterion standard established by the United States Agency for Healthcare Research and Quality: middle-ear effusion (MEE) plus onset in the past 48 h of signs or symptoms of middle-ear inflammation. A secondary objective was to assess the potential reduction in antibiotic usage that could be achieved if clinicians managed AOM according to a consensus guideline developed by the New York Region Otitis Project (NYROP). A convenience sample of primary care practitioners were surveyed after diagnosing AOM in 135 children aged 0.3-11.8 years (median 2.4 years). Clinicians expressed high certainty for AOM diagnosis in 122/135 episodes (90%). The prevalence of true AOM was 70% with a positive predictive value for high certainty of 76%. Of the 40 false-positive diagnoses, 35 did not have MEE and 5 did not have acute signs or symptoms. The relative risk for receiving an antibiotic was 1.50 times higher when clinicians expressed certainty (P=0.005), which produced 31/120 (26%) potentially unnecessary antibiotic prescriptions. Initial antibiotics would not have been prescribed for 29% of episodes using the NYROP guidelines. More judicious use of antibiotics may result if clinicians deferred initial therapy in children without definitive AOM, particularly when the presence of MEE is uncertain.