Peer Comparison Feedback As An Antimicrobial Prescribing Intervention To General Medicine Specialists

Antimicrobial resistance (AMR) is a critical threat to human health, having led to the deaths of 14,000 people in Canada in 2018 and 1.25 million people globally in 2019. There has been limited success in overcoming AMR through developing new antimicrobials, primarily due to inadequate investment in new antimicrobial discovery, and economic and regulatory hurdles. Acquired resistance is also likely to occur as newer agents come to market. The World Health Organization and the Public Health Agency of Canada have identified overuse of antimicrobials as a primary ongoing driver of AMR. Therefore, optimizing antimicrobial use must be a cornerstone of our response to the AMR crisis.

Antimicrobial stewardship (AMS) interventions (activities designed to safely improve antimicrobial use) can lead to reductions in antimicrobial use, antimicrobial costs, hospital length of stay, and C. difficile rates. Previous work has demonstrated that audit and feedback with peer comparison in a primary care setting can lead to a clinically significant reduction in antimicrobial use, with no demonstrable safety concerns. For example, the study team previously tested a peer comparison letter to primary care providers in the highest quartile of antimicrobial prescribing across Ontario and found a clinically significant 4% relative reduction in total antimicrobial prescribing. This extrapolates to nearly 150,000 fewer prescriptions and drug-cost savings of $2.7 million annually for the province.

General medicine wards are an important target for antimicrobial stewardship efforts, as they care for the largest group of hospital inpatients, patients are often medically complex, and admissions are heterogeneous in condition/disease. However, physician-level prescribing data for hospitalized patients has historically been difficult to collect and attribute to a specific clinician, limiting rigorous evaluation. This trial will leverage GEMINI's pharmacy data to create physician-level peer-comparison reports for physicians practicing on general medical wards. Building on a previous CIHR-funded RCT led by Drs. Desveaux and Ivers, this trial will also develop a mixed methods process evaluation methodology to assess fidelity and mechanism of action.

• Initiation of antimicrobial therapy [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• Discontinuation of antimicrobial therapy within 72 hours [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• Antimicrobial-free days [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• Antimicrobial choice [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• Mechanism of action (interview) [Time frame: This process evaluation outcome will be measured within 12 months of the intervention delivery (i.e., during the follow-up period).]
• Fidelity of receipt (survey) [Time frame: This process evaluation outcome will be measured within 12 months of the intervention delivery (i.e., during the follow-up period).]
• Fidelity of implementation (survey) [Time frame: This process evaluation outcome will be measured within 12 months of the intervention delivery (i.e., during the follow-up period).]
• In-hospital mortality [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• Readmission within 7 days [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• ICU admissions [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]
• Inpatient LOS (length of stay) [Time frame: All secondary outcomes will be measured for 24 month prior to intervention delivery (i.e., the baseline period) and for 12 months after intervention delivery (i.e., the follow-up period).]