Integrated antibiotic clinical decision support system (CDSS) for appropriate choice and dosage: an analysis of retrospective data.

Introduction: Decision-making for inpatient antibiotic prescribing is complex due to many considerations to be taken. So far, clinical decision support systems (CDSS) have been rarely used in antibiotic stewardship (ABS) and even less integrated in computerized physician order entry systems (CPOE). Methods: We developed a guideline-based, CPOE-integrated CDSS (ID ANTIBIOTICS) to support antibiotic selection and dosing. We compared routine antibiotic inpatient prescribing data with CDSS-generated recommendations in the initial antibiotic selection, the duration of therapies, and costs. Finally, we assessed possible benefits of the CDSS by its performance in German ABS-guideline quality indicators (ABS-QIs). Results: The requirements of several ABS-QIs can be supported with ID ANTIBIOTICS: electronic local guidelines, electronic decision-support, renal dosage adjustments, local guideline-based initial selection (all not quantified), and therapy durations for the treatment of pneumonia (significantly) without increasing costs. Performance in ABS-QIs for extensive therapies for community-acquired pneumonia could be improved with the CDSS by 20.2% (OR 0.134; 95% CI: 0.101-0.178); for hospital-acquired pneumonia by 3.7% (OR 0.742; 95% CI: 0.629-0.877). There was no difference in median daily drug costs between real-world prescriptions and CDSS recommendations (both: € 4.78, p=0.081). Conclusions: In retrospective analyses, antibiotic CDSS can show possible performance in antibiotic stewardship through quality indicators (ABS-QIs). Further research and pilot testing of the software are needed to provide more insights into ABS-QI evaluation, user acceptance, and real-world effectiveness. Deep integration of antibiotic CDSS into existing medication processes without using multiple systems could contribute to the necessary acceptance of clinical practitioners.