Impact of the ABxSG Mobile Application on Antibiotic Prescribing: An Interrupted Time Series Study

A point prevalence survey conducted at Singapore General Hospital in 2021 showed 48% of inpatients on antibiotics. We hypothesize that a mobile application, transforming complex antibiotic prescribing information into a succinct and individualized resource, will empower healthcare professionals and improve antibiotic prescriptions. Hence, we developed ABxSG using the behavioral design thinking approach (BDTA) to ensure positive user experience and sustained engagement. We aim to evaluate the impact of ABxSG on the proportion of inpatients on antibiotics, antibiotic appropriateness, and the number of antibiotic-related interventions by pharmacists.

ABxSG was launched in March 2023. An interrupted time series analysis was conducted to evaluate its impact on the above outcomes measured using data collected from October 2021 to September 2024. There were 18 data points pre- and post-ABxSG.

Following the ABxSG launch, there was an immediate reduction in the proportion of inpatients on antibiotics by 1.66% (p < 0.01), followed by a sustained reduction of 3.12% at 18 months (p < 0.01). Piperacillin-tazobactam appropriateness increased by 2.76% at 1 month (p = 0.11) and further increased by 7.09% at 18 months (p < 0.05). Similarly, ceftriaxone appropriateness increased by 5.74% (p < 0.05) at 1 month and remained above pre-ABxSG levels. There was a significant increase in the number of pharmacist-led interventions for dosing optimization, with 96 more interventions/month at 18 months (p = 0.14).

Antimicrobial stewardship teams must remain agile, embrace innovations, and adopt digital technologies to engage and empower clinicians. ABxSG reduced the proportion of inpatients on antibiotics and improved antibiotic prescriptions. The incorporation of BDTA in ABxSG, strong hospital leader support, and strategic planning to promote adoption led to its success.