Imaging Decision Support Does Not Drive Out-of-Network Leakage of Referred Imaging

Leakage (out-of-network referral) is undesirable because it limits ability to control costs of services. Clinical decision support (CDS) systems seek to ensure appropriate imaging of patients but theoretically could drive leakage if ordering providers attempt to circumvent CDS recommendations and obtain studies from other imaging providers. This study assessed the incidence of leakage of imaging studies that had low appropriateness scores.

We queried our outpatient CDS system over a three-year period (2011-2013) for studies that received a low CDS appropriateness score and were canceled by the ordering physician. For patients meeting these criteria and participating in risk-shared contracts, we cross-referenced their imaging utilization reports in the risk-contract insurance payment database to determine if they received outpatient imaging within 60 days of the index order, contrary to the decision support recommendation.

The risk-shared insurance database contained an average of 63,378 patients who had 18,008 MRIs and 18,014 CTs. A total of 11,234 (31.2%) studies were leaked: 3,513 (9.8%) to affiliated institutions; 7,721 (21.4%) to unaffiliated imaging facilities. Overall, 111 imaging studies received a low appropriateness score in the risk-shared patient population and were performed within 60 days despite the low score. Of these studies, 106 of 111 (95.5%) were ultimately performed within our hospital system (104 at the home institution; 2 at affiliated institutions); only 5 of 111 (4.5%) were performed outside of our hospital system.

Decision support systems for ordering providers do not seem to drive imaging referrals out of hospital systems to other institutions. Hospital systems can implement decision support without fear of this occurring.