Correlation Between Large-Scale Health System Operational Parameters and Laboratory Test Utilization

Abstract

Abstract Introduction/Objective The extent of correlation between clinical laboratory test utilization and large-scale operational parameters would be helpful to adjust for these parameters when benchmarking utilization. Methods/Case Report We compared clinical laboratory and imaging utilization over 3 years (2019-2021) for adult patients hospitalized for specific surgical, medical, and obstetrics diagnoses at multiple academic hospitals (N=58; 625,436 hospitalizations) ranging in size from 250-1300 hospital beds. We queried the Vizient Clinical Data Base with permission from Vizient, Inc.® employing Medicare Severity Diagnosis Related Groups (MSDRG), used by the US Centers for Medicare and Medicaid Services (CMS), to identify hospitalizations for gastrointestinal (GI) surgery (MSDRG triplet 329/330/331), sepsis (MSDRG triplet 870/871/872), and vaginal delivery (MSDGR triplet 805/806/807). We stratified patients within each diagnostic group for comorbid conditions and complications into high, moderate, and low severity groups. We compared mean laboratory tests and Resource Intensity Weight (RIW) per hospitalization and hospital day. The RIW is based on the CMS Ambulatory Payment Classification (APC) weights. We measured correlation of laboratory utilization with hospital bed size as well as annual discharges (sepsis group), surgical procedures (GI surgery group), births (vaginal delivery group), and diagnosis-specific discharges. Results (if a Case Study enter NA) For sepsis hospitalizations, there were small significant (p<.01) negative correlations (r2 0.05-0.16) between laboratory utilization, measured as test numbers or RIW, and diagnosis-specific discharges for low and moderate severity groups; there was no significant correlation with either bed size or overall annual discharges. There were no consistent correlations of laboratory utilization with bed size, annual surgical procedures, or diagnosis-specific discharges for GI surgery patients. Hospitalizations for vaginal delivery demonstrated small negative correlations between laboratory utilization and bed size, annual births, and diagnosis- specific discharges. Conclusion For specific diagnostic groups, laboratory utilization (tests as well as laboratory RIW) exhibited negative correlations with large-scale hospital operational parameters. These correlations were typically weak with varying statistical significance. The findings suggest that laboratory test utilization efficiency may require evaluation of individual health systems on a case-by-case basis.