Benchmarking to Identify Practice Variation in Test Ordering: A Potential Tool for Utilization Management

Background: Appropriate test utilization is usually evaluated by adherence to published guidelines. In many cases, medical guidelines are not available. Benchmarking has been proposed as a method to identify practice variations that may represent inappropriate testing. This study investigated the use of benchmarking to identify sites with inappropriate utilization of testing for a particular analyte. Methods: We used a Web-based survey to compare 2 measures of vitamin D utilization: overall testing intensity (ratio of total vitamin D orders to blood-count orders) and relative testing intensity (ratio of 1,25(OH)(2)D to 25(OH)D test orders). Results: A total of 81 facilities contributed data. The average overall testing intensity index was 0.165, or approximately 1 vitamin D test for every 6 blood-count tests. The average relative testing intensity index was 0.055, or one 1,25(OH)(2)D test for every 18 of the 25(OH)D tests. Both indexes varied considerably. Conclusions: Benchmarking can be used as a screening tool to identify outliers that may be associated with inappropriate test utilization.