A study to assess the impact of cobas Liat point-of-care PCR assays (SARS-CoV-2 and Influenza A/B) on patient clinical management in the emergency department of the University of California at Davis Medical Center

Background Rapid detection of SARS-CoV-2 is crucial for reduction of transmission and clinical decision-making. The cobas® SARS-CoV-2 & Influenza A/B nucleic acid test for use on the cobas Liat® System is a rapid (20 minutes) point-of-care (POC) polymerase chain reaction (PCR) method. Methods This unblinded, pre-post study enrolled consecutive patients with symptoms/signs consistent with SARS-CoV-2 infection presenting to the University of California, Davis emergency department (ED). Outcomes following implementation of the cobas Liat SARS-CoV-2 & Influenza A/B test (intervention period: December 2020–May 2021) were compared with previous standard-of-care using centralized laboratory PCR methods (control period: April 2020–October 2020). Results Electronic health records of 8879 symptomatic patients were analyzed, comprising 4339 and 4540 patient visits and 538 and 638 positive SARS-CoV-2 PCR test results in the control and intervention periods, respectively. Compared with the control period, turnaround time (TAT) was shorter in the intervention period (median 0.98 vs 12.3 hours; p<0.0001). ED length of stay (LOS) was generally longer in the intervention period compared with the control period, but for those SARS-CoV-2-negative who were admitted, ED LOS was shorter (median 12.53 vs 17.93 hours; p<0.0001). Overall, the rate of anti-infective prescribing was also lower in the intervention period than in the control period (antibiotics only: 38.11% vs 44.55%; p<0.0001 and antivirals only: 3.13% vs 0.94%; p<0.0001). Conclusion This real-world study confirms faster TAT with a POC PCR method in an emergency care setting and highlights the importance of rapid SARS-CoV-2 detection to aid patient management and inform treatment decisions. Clinical Relevance This study reports data collected from a quasi-experimental pre-post study using the electronic health records of patients presenting to the emergency department (ED) of the University of California at Davis Medical Center with symptoms or signs consistent with SARS-CoV-2 infection during their ED visit. The primary objective of this study was to determine if implementation of the point-of-care (POC) cobas® Liat® SARS-CoV-2 & Influenza A/B test for use on the cobas Liat System reduced the diagnostic turnaround time and/or length of stay for ED patients with suspected SARS-CoV-2 infection compared with the previous standards of care (batch-wise diagnostic testing using the cobas 6800 System and on-demand urgent testing on the GenMark Dx® ePlex® system in a centralized clinical laboratory). Ultimately, these data help to inform how implementation of POC molecular testing methods impact patient management. ### Competing Interest Statement EMR, JAC, and KC are employees of Roche Molecular Systems Inc., and EMR holds company stock. LM and NKT have received payment or honoraria for lectures, presentations, or advisory boards from Roche Molecular Systems, Inc., and LM has received honoraria from Roche Diagnostics Solutions. ### Funding Statement This study was funded by Roche Molecular Systems, Inc. Medical writing support was provided by Samantha Forster of Elements Communications Ltd (Westerham, UK) and was funded by Roche Molecular Systems, Inc. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: This study was conducted in compliance with the International Conference on Harmonisation Good Clinical Practice Guidelines, and applicable US Food and Drug Administration regulations. The study protocol and de-identification procedure for patient data were approved by the UC Davis Institutional Review Board Administration. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes xI have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes The data used to support the findings of this study are included within the article and supplementary materials.