Effects of a nudge-based antimicrobial stewardship program in a pediatric primary emergency medical center

Outpatient medical facilities tend to have high antimicrobial prescription rates and are therefore major targets for antimicrobial stewardship programs (ASPs). Pediatric primary emergency medical centers in Japan have difficulties in implementing conventional ASPs due to the low continuity of stewardship. Accordingly, there is a need to develop effective ASP models for these facilities. We conducted a single-center, quasi-experimental study to evaluate the effects of a nudge-based ASP in reducing unnecessary third-generation cephalosporin (3GC) prescriptions in a pediatric primary emergency care center (PEC). The implemented ASP utilizes monthly newsletters that report current antimicrobial use patterns and prescribing targets. We compared the monthly 3GC prescription numbers and proportions of unnecessary prescriptions before and after the ASP was implemented. The trends in 3GC prescriptions were examined using an interrupted time-series analysis. The numbers of patients before and after ASP implementation were 129,156 and 28,834, respectively. The number of unnecessary 3GC prescriptions decreased by 67.2% in the year after ASP implementation. The interrupted time-series analysis showed that the ASP was significantly associated with a reduction in 3GC prescriptions (regression coefficient - 0.58, P < 0.001).Conclusion: The nudge-based ASP was effective in reducing 3GC use in a Japanese PEC. This simple and inexpensive approach may have applications in other outpatient facilities. What is Known: • Outpatient medical facilities tend to have high antimicrobial prescription rates. Despite the development of several strategies for outpatient antimicrobial stewardship programs, these approaches have not sufficiently reduced antimicrobial use. What is New • Our nudge-based antimicrobial stewardship program using newsletters was shown to be a simple, inexpensive, and feasible method for reducing unnecessary antimicrobial use in a pediatric primary emergency care center. This may represent an effective antimicrobial stewardship strategy in Japanese outpatient facilities.