Potentially redundant repeat liver function test ordering practices in australian hospitals: A 5‐year multicentre retrospective observational study

BACKGROUND: Repeat Liver Function Tests (LFTs) are often necessary for monitoring purposes, but retesting within a short time interval may suggest potentially redundant repeat test (PRRT) ordering practices. We aimed to determine the proportion of potentially redundant repeat LFT ordering and identify associated factors in hospitals. METHODS: A 5‐year (2014‐2018) retrospective cohort study in six hospitals in New South Wales, Australia. A total of 131 885 patient admissions with repeat LFTs in the general ward (n = 102 852) and intensive care unit (ICU) (n = 29 033) met the inclusion criteria. Existing guidelines do not support retesting LFT for at least 48‐72 hours. We used 24 hours as a conservative minimum retesting interval to examine PRRT ordering. We fit binary logistic regression to identify factors associated with PRRT ordering in two conditions with the highest repeat LFTs. RESULTS: There were a total of 298 567 repeat LFTs (medians of 2 repeats/admission and retesting interval of 25.6 hours) in the general ward and 205 929 (medians of 4 repeats/admission and retesting interval of 24.1 hours) in the ICU. The proportions of PRRT ordering were 35.2% (105 227/298 567) and 47.7% (98 307/205 929) in the general ward and ICU, respectively. The proportions of patients who received at least one PRRT were 52.3% (53 766/102 852) and 83.9% (24 365/29 033) in the general ward and ICU, respectively. Age, gender and the number of comorbidities and procedures were associated with the likelihood of ordering PRRT depending on the settings. CONCLUSION: Repeat LFT testing is common in Australian hospitals, often within 24 hours, despite guidelines not supporting too‐early repeat testing. Further research should be conducted to understand whether better adherence to existing guidelines is required, or if there is any case for guidelines to be updated based on certain patient subpopulations.