BACKGROUND:Antimicrobial stewards may benefit from comparative data to inform interventions that promote optimal antimicrobial use in the inpatient setting. METHODS:Antimicrobial stewards from eight geographically dispersed Veterans Affairs (VA) inpatient facilities participated in the development of iterative antimicrobial use visualization tools that allowed for comparison to facilities of similar complexity. The visualization tools consisted of an interactive web-based antimicrobial dashboard and, later, a standardized antimicrobial usage report updated at user-selected intervals. Following tool implementation, stewards participated in monthly learning collaboratives. The percent change in average monthly antimicrobial use [all antimicrobial agents, anti-methicillin-resistant Staphylococcus aureus agents (anti-MRSA), and anti-pseudomonal agents] was analyzed using a pre-post (1/2014-1/2016 versus 7/2016-1/2018) design with segmented regression and external comparison with uninvolved control facilities (n=118). RESULTS:Intervention sites demonstrated a 2.1% decrease (95% confidence interval (CI) [-5.7%, 1.6%]) in total antimicrobial use pre-post intervention, versus a 2.5% increase (95% CI [0.8%, 4.1%]) in non-intervention sites (absolute difference 4.6%, P=0.025). Anti-MRSA antimicrobial use decreased 11.3% (95% CI [-16.0%, -6.3%]) at intervention sites versus a 6.6% decrease (95% CI [-9.1%, -3.9%]) at non-intervention sites (absolute difference 4.7%, P=0.092). Anti-pseudomonal antimicrobial use decreased 3.4% (95% CI [-8.2%, 1.7%]) at intervention sites versus a 3.4% increase (95% CI [0.8%, 6.5%]) at non-intervention sites (absolute difference 7.0%, P=0.018). CONCLUSIONS:Comparative data visualization tool use by stewards in a pilot implementation project at eight VA facilities was associated with significant reductions in overall antimicrobial and anti-pseudomonal use relative to uninvolved facilities.