CT scan use varies greatly between docs in same ED

Researchers at Brigham & Women's Hospital in Boston have found that CT scan use, specifically for the head, varies greatly in a single emergency department setting, according to a study set for publication in the April edition of the American Journal of Medicine. The results are particularly intriguing given the recent press surrounding the costs and drivers of medical imaging.

According to Luciano Prevedello, M.D., the study's lead author, the variability--which was more than two-fold for head CT ordering overall, and three-fold for scans performed on patients with non-traumatic injuries--could have been due to any number of factors, including a particular doctor's practice preferences and risk tolerance. Prevedello said in a statement that he and his colleagues will also study how clinical decision support via electronic health records impacts testing patterns.

The study examined more than 55,000 ED patient encounters, and found that slightly more than 4,900 (8.9 percent) involved head CT exams. Overall, unadjusted CT ordering rates per physician ranged from 4.4 percent to 16.9 percent; for patients with non-traumatic headaches, the rates jumped to between 15.2 percent and 61.7 percent.

Interestingly, a study published last month in the Annals of Emergency Medicine found that a measure created by the Centers for Medicare & Medicaid Services that tests the necessity of CT scans for non-trauma related patients is misleading and unreliable. The measure, known as Outpatient Measure 15 (OP-15) used information culled from Medicare administrative data to try to determine the need for a CT scan. Researchers determined the accuracy of the measure to be 16.7 percent.

For more information:
- here's the American Journal of Medicine study abstract
- read the accompanying announcement
- check out the Annals of Emergency Medicine study abstract