Variation in use of all types of computed tomography by emergency physicians

Variation in computed tomography (CT) use between emergency medicine (EM) physicians may delineate appropriate or inappropriate use. We hypothesize that variation in all types of CT use exists between providers and their use in patients with common chief concerns. We determine EM physicians' variability in CT use of all types and whether high use in one area predicts use of other CT types.

This was a retrospective study of EM physicians practicing at an 800-bed tertiary level 1 trauma center over a 3.5-year period. Computed tomography rates by type and by patient chief concern were modeled for providers as a function of patient acuity, disposition, age, and time of day using logistic regression.

Of 195 801 eligible visits, 44 724 visits resulted in at least 1 CT scan. The adjusted rate of CT ordering by providers was 23.8% of patient visits, ranging from 11.5% to 32.7% The upper quartile of providers was responsible for 78% of the CT scans ordered above the mean. There was a large variation in use of all types of CT and by chief concern. There was an 8-fold variation in use of CT abdomen in discharged patients. High head CT use by providers predicts high use in all other CT types.

We demonstrate a dramatic variation in CT use among EM physicians in all types of CT and common chief concerns. Greater variation was present in patients who were discharged. Large deviation from the mean by a group of providers may suggest inappropriate use.