To test or to not test: A retrospective cross-sectional study on potentially inappropriate use of pathology testing in South Australian hospitals.

OBJECTIVES: To measure rates of potentially inappropriate pathology testing in the hospital setting. METHODS: Retrospective cross-sectional study in hospital setting from July 2021 to December 2021. We examined 3 potentially inappropriate uses: overordering, selection errors, and unnecessary repeat testing. Overordering included vitamin D and lipids (rarely required in acute hospital care). Selection error was the ratio of iron studies to standalone ferritin requests. Unnecessary repeats included any repeat vitamin D, lipids, iron, or ferritin in an episode of care or C-reactive protein (CRP) repeated within 3 days and N-terminal pro-brain natriuretic peptide (NT-proBNP) within 7 days and repeated previously abnormal CRP and NT-proBNP tests. Costs of inappropriate tests were estimated using the Australian Medicare Benefits Schedules. RESULTS: Among 55,904 test requests, 15% (n = 8120) were potentially inappropriate. Vitamin D was frequently ordered (n = 4498), as were lipids (n = 2872). Ratio of iron studies to standalone ferritin was 36. Of 19,233 repeat CRPs, 36% (n = 6947) were within 3 days and 62% (n = 179) of repeat NT-proBNPs were within 7 days of the first test. For initially abnormal tests, 89% of CRPs and 97% of NT-proBNPs remained abnormal. Inappropriate test costs accounted for 12% to 30% of costs. CONCLUSIONS: Frequent potential inappropriate use and selection of pathology tests was observed in South Australian hospitals.

Introducing First-Year Undergraduate Students the Fundamentals of Antibiotic Sensitivity Testing through a Combined Computer Simulation and Face-to-Face Laboratory Session.

Determining the antibiotic sensitivity of disease-causing microorganisms is a fundamental process in a clinical microbiology laboratory. With the continued use of antibiotics, the emergence of antibiotic resistance has become a significant health issue. However, the principles and laboratory testing to determine antibiotic sensitivity are generally not taught to first-year undergraduate students. This is partly due to the limited time to cover the fundamental biology of microorganisms and the mechanism of action of antibiotics in an introductory course. We overcame these limitations by teaching first-year students the fundamental principles of antibiotic sensitivity using an online data generator/simulation. Using the Kirby-Bauer disk diffusion test, students replicated the effects of antibiotic dose on bacterial growth and determined the antimicrobial susceptibility testing of their allocated bacterium. After 2-3 weeks, the antimicrobial sensitivity testing was replicated in an authentic face-to-face laboratory setting over 2 days. The impact of the intervention on student learning was assessed using a written laboratory report and a short questionnaire containing Likert and free-text questions. Student self-reported understanding of the content rose significantly, with nearly all students passing the written assessment. The approach was found to be enjoyable and interactive and facilitated authentic learning in first-year students. This cohort of students will continue to use more advanced versions of this simulation in future years, allowing for the long-term benefits of this approach to be assessed.