Predictors of provider response to clinical decision support: Lessons learned from the medicare imaging demonstration

OBJECTIVE. The efficacy of imaging clinical decision support (CDS) varies. Our objective was to identify CDS factors contributing to imaging order cancellation or modification. SUBJECTS AND METHODS. This pre-post study was performed across four institutions participating in the Medicare Imaging Demonstration. The intervention was CDS at order entry for selected outpatient imaging procedures. On the basis of the information entered, computerized alerts indicated to providers whether orders were not covered by guidelines, appropriate, of uncertain appropriateness, or inappropriate according to professional society guidelines. Ordering providers could override or accept CDS. We considered actionable alerts to be those that could generate an immediate order behavior change in the ordering physician (i.e., cancellation of inappropriate orders or modification of orders of uncertain appropriateness that had a recommended alternative). Chi-square and logistic regression identified predictors of order cancellation or modification after an alert. RESULTS. A total of 98,894 radiology orders were entered (83,114 after the intervention). Providers ignored 98.9%, modified 1.1%, and cancelled 0.03% of orders in response to alerts. Actionable alerts had a 10 fold higher rate of modification (8.1% vs 0.7%; p < 0.0001) or cancellation (0.2% vs 0.02%; p < 0.0001) orders compared with nonactionable alerts. Orders from institutions with preexisting imaging CDS had a sevenfold lower rate of cancellation or modification than was seen at sites with newly implemented CDS (1.4% vs 0.2%; p < 0.0001). In multivariate analysis, actionable alerts were 12 times more likely to result in order cancellation or modification. Orders at sites with preexisting CDS were 7.7 times less likely to be cancelled or modified (p < 0.0001). CONCLUSION. Using results from the Medicare Imaging Demonstration project, we identified potential factors that were associated with CDS effect on provider imaging ordering; these findings may have implications for future design of such computerized systems.