Interrupted time-series analysis to evaluate the impact of a behavioral change outpatient antibiotic stewardship intervention.

Objective: We evaluated the effect of a behaviorally enhanced quality improvement intervention in reducing the number of antibiotic prescriptions written for antibiotic nonresponsive acute respiratory infections (ARIs). A secondary objective was identifying whether a reduction in inappropriate antibiotic prescriptions, if present, persisted after the immediate implementation of the intervention.

Design: Nonrandomized, quasi-experimental study conducted from January 2017 through February 2020.

Setting: University of California, Davis Health outpatient clinics. In total, 21 pediatric, family, and internal medicine practices in 10 cities and towns were included.

Patients: Patients evaluated by a participating physician at an enrolled practice site during the study period with diagnoses (primary and secondary) from the codes consistent with antibiotic nonresponsive ARI diagnoses.

Intervention: A behaviorally enhanced quality improvement intervention to reduce inappropriate prescribing for antibiotic nonresponsive ARI.

Results: In total, 63,028 eligible patient visits across 21 locations were included in the analysis. The most frequently prescribed antibiotic for antibiotic nonresponsive ARI was azithromycin (n = 3,551), followed by amoxicillin (n = 924). Overall, the intervention was associated with an immediate 46% reduction in antibiotic prescriptions for antibiotic nonresponsive ARI ( = .001) following the intervention. We detected no significant change in the month-to-month trend after the intervention was implemented ( = .87), indicating that the reduction was sustained throughout the postintervention period.

Conclusion: Our findings demonstrate that a behaviorally enhanced quality improvement intervention to reduce inappropriate prescribing for antibiotic nonresponsive ARI in ambulatory care encounters was successful in reducing potentially inappropriate prescriptions for presumed antibiotic nonresponsive ARI.