Background: Drug-drug interaction (DDI) alerts in electronic health records (EHRs) can help prevent adverse drug events, but such alerts are frequently overridden, raising concerns about their clinical usefulness and contribution to alert fatigue.
Objective: To study the effect of conversion to a commercial EHR on DDI alert and acceptance rates.
Design: Two before-and-after studies.
Participants: 3277 clinicians who received a DDI alert in the outpatient setting.
Intervention: Introduction of a new, commercial EHR and subsequent adjustment of DDI alerting criteria.
Main measures: Alert burden and proportion of alerts accepted.
Key results: Overall interruptive DDI alert burden increased by a factor of 6 from the legacy EHR to the commercial EHR. The acceptance rate for the most severe alerts fell from 100 to 8.4%, and from 29.3 to 7.5% for medium severity alerts (P < 0.001). After disabling the least severe alerts, total DDI alert burden fell by 50.5%, and acceptance of Tier 1 alerts rose from 9.1 to 12.7% (P < 0.01).
Conclusions: Changing from a highly tailored DDI alerting system to a more general one as part of an EHR conversion decreased acceptance of DDI alerts and increased alert burden on users. The decrease in acceptance rates cannot be fully explained by differences in the clinical knowledge base, nor can it be fully explained by alert fatigue associated with increased alert burden. Instead, workflow factors probably predominate, including timing of alerts in the prescribing process, lack of differentiation of more and less severe alerts, and features of how users interact with alerts.
Keywords: adverse drug events; clinical decision support; drug-drug interactions; electronic health records; safety.