Process evaluation of an effective Antimicrobial Stewardship intervention in hospitalized patients with community-acquired pneumonia

Objective: In a previously conducted stepped-wedge cluster randomized trial, a multicomponent Antimicrobial Stewardship intervention reduced mean duration of broad-spectrum antimicrobial treatment by 26.6% (from 6.5 to 4.8 days) in patients with moderate-severe community-acquired pneumonia (CAP). This study presents a detailed process evaluation of the multicomponent Antimicrobial Stewardship improvement intervention. Methods: The intervention consisted of educational activities (clinical lessons with prescription feedback, e-learning, pocket cards, and poster), local opinion leaders promoting guideline-adherent treatment, and prospective audit and feedback. The experiences with performing the intervention were evaluated using trial data; exposure data (clinical lessons, e-learning, and prospective audit and feedback); and semi-structured interviews conducted in December 2019 with eleven physicians from four hospitals. Results: Most intervention components were conducted as planned. However, clinical lessons and e-learning were scheduled more frequently, while prospective audit and feedback was temporarily interrupted in some hospitals. Clinical lessons were on average attended by 31% of the target audience and 44% completed the e-learning. Feedback was provided in 56% of patients receiving broad-spectrum antimicrobials. Clinical lessons, prospective audit and feedback, and local opinion leaders, were identified as the most effective components. Pocket cards were regarded as easy to implement. While e-learning content was judged useful, its perceived effectiveness was reduced by "e-learning fatigue." The poster was considered of low effectiveness. Conclusion: Based on participant experiences, key components of an effective stewardship intervention for improving antimicrobial use in hospitalized CAP patients included prospective audit and feedback, clinical lessons with prescription feedback, pocket cards, and actively engaged local opinion leaders.