Impact of infection control measures on the related costs and the amount of broad‐spectrum antimicrobial agents used in a hospital: A time‐series analysis

Health care–associated infections (HAIs) worsen patient prognoses and increase medical costs. Antimicrobial stewardship (AMS), which involves appropriate use of antimicrobial agents and antiseptics, may be beneficial for addressing the issue of HAIs. In hospitals, an infection control team (ICT) plays an important role on the appropriate use of antimicrobial agents and antiseptics based on AMS. We aimed to conduct a time‐series analysis of the efficacies of infection control measures in terms of related costs, amount of broad‐spectrum antimicrobial agents used (carbapenems and quinolones), and methicillin‐resistant Staphylococcus aureus (MRSA) detection rates. This retrospective cross‐sectional study included in‐hospital patients treated at a single institute between January 2012 and December 2015. The intervention start point (initiation of infection control measures) was January 2014. All survey items were subjected to segmented regression analysis using an autoregressive integrated moving average (ARIMA) model. Differences between pre‐intervention and postintervention levels and their trends were assessed, using a statistical significance cutoff of P