Increased Resource Utilization
At Vanderbilt, Rosenbloom et al. evaluated 3 successive interventions designed to reduce serum magnesium test ordering through a care provider order entry system. They monitored weekly rates of new serum magnesium test orders, instances, and results. The 3 interventions in order of their application:
- Exhorted users to discontinue unnecessary tests recurring more than 72 hours into the future.
- Displayed recent magnesium, calcium and phosphorus test results, limited testing to one test instance per order, and provided education regarding appropriate indications for testing.
- Targeted only magnesium ordering, displayed recent results, limited testing to one instance per order, summarized indications for testing, and required users to select an indication.
At baseline, there were 539 magnesium tests ordered per week. This decreased to 380 (P=0.001) per week after the first intervention, increased to 491 per week (P<0.001) after the second, and decreased to 276 per week (P<0.001) after the third.
Summary: A clinical decision support intervention intended to regulate testing increased test order rates as a result of unintended decision support. CPOE implementers must carefully design resource-related interventions and monitor their impact over time.
Rosenbloom ST, Chiu KW, Byrne DW, Talbert DA, Neilson EG, Miller RA. Interventions to Regulate Ordering of Serum Magnesium Levels: an unintended consequence of decision support. J Am Med Inform Assoc. 2005 May 19;