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 International Classification of Diseases, Tenth Revision 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 (P = .001) following the intervention. We detected no significant change in the month-to-month trend after the intervention was implemented (P = .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.