Doing more with less: a narrative review of recent evidence in diagnostic stewardship

Diagnostic stewardship (DS) aims to optimise the use of laboratory testing to improve patient care while reducing unnecessary tests. This review examines recent evidence on DS interventions to optimise the use of resources, focusing on three key areas: reducing unnecessary testing, maximising the impact of existing tests, and avoiding the overdiagnosis of hospital-acquired infections.

Multiple interventions have demonstrated effectiveness in reducing unnecessary blood and urine culture testing, including clinical decision support tools, education programs, and multidisciplinary approaches. Studies on optimising existing tests have focused on blood culture workflows, reporting of nonsterile samples, and implementation of multiplex PCR panels. Interventions to reduce overdiagnosis of catheter-associated urinary tract infections and Clostridioides difficile infection have shown promise. However, the monitoring of unintended consequences varies across studies. Most publications were retrospective cohort studies, with few randomized trials.

DS can safely reduce inappropriate testing and maximise test effectiveness. Successful implementation requires multidisciplinary engagement and careful monitoring of the unintended consequences. Further high-quality studies, especially randomised trials, are needed to assess the clinical impact of DS interventions robustly.