Implementing effective test utilization via team-based evaluation and revision of a family medicine laboratory test requisition

Abstract

INTRODUCTION Revision of laboratory test requisitions is a simple utilisation strategy that can reduce unnecessary testing.1 2 The goal of this study was to improve test utilisation via a collaborative team-based evaluation and revision of a standardised lab requisition used by six large family medicine units. METHODS Revising the family requisition form A historical laboratory requisition used by the Family Medicine Department at Unity Health, St. Michael's Hospital site, Unity Health Toronto, Toronto, Canada, was reviewed and modified by a steering committee comprised of family medicine clinicians (physicians and a nurse practitioner), lab medicine specialists and a quality improvement specialist. Decisions were made by consensus, and input was sought from the entire Department of Family Medicine via departmental rounds before changes were finalised. Laboratory tests were removed from the requisition if there was evidence in the literature of overuse (eg, Aspartate Aminotransferase (AST), folate, urea, Erythrocyte Sedimentation Rate (ESR),3 4 if they were outdated (eg, amylase, Creatine Kinase (CK)),3 or if there was consensus that they were infrequently needed in a family practice (eg, rheumatoid factor, direct bilirubin). The requisition was also revised to improve readability, and education was imbedded regarding some special tests such as urine toxicology screening and coagulation testing (changes in online supplemental table 1). Tests that were removed from the requisition remained orderable with longhand. Data analyses The primary outcome was the monthly volume of targeted tests ordered by the family medicine clinic 6 months pre-and 6 months post-requisition changes (September 2018 to September 2019). The proportion of abnormal test results and the ratio of Alanine Aminotransferase (ALT) (not targeted) to AST (targeted) were used as balance measures. Outpatient monthly laboratory test volumes for 20 tests were extracted from the laboratory information system. Process Control charts were generated using GraphPad Prism V.8.2.0. The proportion of abnormal results was calculated using R studio program V.1.2.5033. A two-tailed t-test was used to explore whether testing volumes were significantly different pre-requisition changes compared to post-requisition changes. Nontargeted tests (eg, ALT, total bilirubin, creatinine, haemoglobin) were used as negative controls. Cost analysis was performed using the Ontario Health Insurance Plan laboratory service fees as an estimate of true cost. The project was formally reviewed by institutional authorities at Unity Health Toronto and deemed to neither require research ethics board approval nor written informed consent from participants. Patients and/or the public were not included in the design, conduct, reporting, or dissemination of our research. RESULTS Ninety-nine thousand four hundred and thirteen laboratory tests were included in this analysis. Modifying the family medicine lab requisition resulted in a significant reduction in volume of targeted tests on AST (-50.8%), direct bilirubin (-68.2%), CK (-31.9%), amylase (-61.2%), urea (-79.9%), ESR (-31.3%), serum folate (-87.2%) and Red Blood Cell (RBC) folate (-76.8%) as depicted in figure 1 and online supplemental table 2. Although medicine requisition only impacted the utilisation of the targeted tests removed. CONCLUSIONS Revision of a family medicine lab requisition was a simple, but effective strategy to decrease unnecessary laboratory testing and improve appropriate testing at our hospital. We recommend reviewing and revising historical requisitions and/or order sets as a way to encourage appropriate lab testing practices.