Background: Variation among hospitalized medical conditions have been reported previously, but there is little information on variation among physicians for medical conditions that constitute a substantial part of ambulatory care.
Objective: To measure variation in the diagnosis of 2 common medical conditions, otitis media (OM) and upper respiratory tract infections (URIs) in an urgent care practice.
Design: Estimate the variation in the incidence of new diagnoses of OM and URIs among 19 physicians working at 2 urgent care clinics between January 1, 1995, and March 31, 1995. Patients are seen in order of arrival, and assignment to each physician is random.
Participants and setting: Two urgent care clinics staffed by the same 19 physicians. During the 3-month study period, 21,259 patients were seen at the 2 clinics; of these, 1839 (8.65%) received a diagnosis of first time OM; and 8020 (37.73%), of an URI.
Main outcome measure: Incidence of new diagnoses of OM and URI estimated as a proportion of all diagnoses for each individual physician.
Results: There was substantial variation between physicians in the diagnosis of OM, ranging from a low of 4.2% to a high of 21.8%. There was less variation in the diagnosis of URI (31.7%-48.4%). Some physicians with a low incidence of OM or URI diagnoses had increased the proportion of diagnoses in the other diagnostic category. For OM the variation was greatest for children younger than age 5 years, but substantial variation was also found in adults. For URIs the variation was more uniform across all age groups. The variation was not explained by type of specialty training or years in medical practice.
Conclusions: There is substantial variation between physicians in their diagnosis of OM and URI in an urgent care setting. This variation has implications for cost of diagnosing and treating these conditions, the training of physicians, and our understanding of the treatment of OM.