Abstract: OBJECTIVE To verify the intervention effect of the FOCUS-PDCA method on improving the pathogen testing submission level before antimicrobial treatment, and to provide empirical support for management policies for the rational use of antimicrobial agents. METHODS Jan. 2023 was set as the intervention time point. The period from Jan. 2022 to Dec. 2022 served as the pre-intervention (control) period, and the period from Jan. 2023 to Jun. 2025 served as the post intervention (management) period. Interrupted time series analysis was employed to evaluate the change in pathogen testing submission rate before and after the intervention. The chi-square test was conducted to analyze changes in the detection rate of multidrug-resistant organisms and the antibiotic use rate. RESULTS After implementing FOCUS-PDCA management, the following pathogen testing submission rates all increased significantly compared to the pre-intervention period (all P<0.001): the rate before treatment with total antimicrobial agents, the rate before treatment with restricted-level agents, the rate before treatment with special-level agents, the targeted pathogen testing submission rate, the rate for hospital-associated infection diagnosis and the rate before combined use of key drugs. The interrupted time series analysis showed that the management measures improved the overall pathogen testing submission level in the short term. In the long term, they increased the pathogen testing submission rate before therapeutic use of antimicrobial agents and the targeted pathogen testing submission rate, with net benefits of 0.93% and 0.72%, respectively (both P<0.05).The detection rate of multidrug-resistant bacteria decreased from 30.76% to 13.19% (P<0.001), with significant reductions in CRKP and CRPA (P<0.05). The usage rate of antimicrobial agents decreased from 30.37% to 25.77% (P<0.001). CONCLUSION The FOCUS-PDCA method, combined with hierarchical management and incentive-restraint mechanisms, effectively improves the pathogen testing submission rate, reduces the MDRO detection rate and promotes high-quality development of healthcare-associated infection management through continuous cycles of improvement.