Long-term Effectiveness of Financial Incentives for Not Prescribing Unnecessary Antibiotics to Children with Acute Respiratory and Gastrointestinal Infections: A Japan’s Nationwide Quasi-Experimental Study

Background To address antibiotic overuse, the Japanese government implemented a novel financial incentive policy in 2018. The policy enables eligible healthcare facilities to claim 800 JPY (≈5.7 USD) per case wherein a rationale to not prescribe antibiotics is offered to children aged <3 years with acute upper respiratory tract infections or gastroenteritis. Although the short-term effect of this policy was observed in our previous study, its long-term effects have not been evaluated nationwide. Methods We conducted a quasi-experimental study using a staggered difference-in-differences design with propensity score matching. Data from 165,113 children born between April 2017 and March 2019 were extracted from two nationwide administrative databases. The study tracked these children until May 2022, comparing those exposed to the policy with those who were not. Results The introduction of financial incentives led to a 44.9% reduction (95%CI, 41.1% to 47.7%) in total antibiotic prescriptions within the first month and 19.5% reduction (95%CI, 8.7% to 29.1%) over 48 months. Broad-spectrum antibiotic use also decreased by 24.4% (95%CI, 14.0% to 33.6%) over the same period. The policy did not result in increased hospitalizations, after-hours visits, or healthcare costs, but was associated with a slight increase in the number of office visits. A dose-response relationship was observed, with reductions in antibiotic use leveling off after approximately five incentives. Conclusions Financial incentives effectively reduced antibiotic prescriptions in children without adverse health outcomes, demonstrating sustained benefits over four years. This antimicrobial stewardship intervention offers a scalable model for other countries aiming to curb antibiotic overuse and combat antimicrobial resistance.