Laboratory Testing for Obstetrics Patients at Academic and Non-Academic Health Systems

Abstract

Introduction/Objective Evaluation of obstetric clinical laboratory test utilization differences between academic and non-academic health systems would provide important benchmarking information for healthcare leaders and policy makers. Methods/Case Report Over a 3-year period (2019-2021), using the Vizient® Clinical Data Base with permission from Vizient, Inc. (All rights reserved.), we compared clinical laboratory utilization for adult obstetrics inpatients at mid-size (250-450 hospital beds) academic (N=9; 27,036 hospitalizations) and non-academic (N=17; 50,462 hospitalizations) hospitals across the US. We used Medicare Severity Diagnosis Related Groups (MSDRG), employed by the US Centers for Medicare and Medicaid Services (CMS), to identify Cesarean section (MSDRG triplet 786-788) and vaginal delivery (MSDGR triplet 805-807) patient groups. For both groups, we stratified by comorbid conditions and complications into high, moderate, and low severity subgroups. We compared the mean number of laboratory tests (CPT codes 80000-89999) per hospitalization and per hospital day. We measured aggregate Clinical Resource Intensity Weight (RIW) per hospitalization to quantify laboratory resource consumption for each encounter. The RIW is based on the CMS Ambulatory Payment Classification (APC) weights. Results (if a Case Study enter NA) Academic hospitals had a significantly (p<.01) higher mean number of lab tests per Cesarean section hospitalization (20.3 vs. 10.3 tests, 97.1% higher) and hospital day (4.7 vs. 3.3 tests, 42.4% higher). Laboratory RIW per case was also significantly (p<.01) higher at academic hospitals (4.8 vs. 3.6 RIW, 33.3% higher); however, RIW per day did not differ between academic and non-academic hospitals. Significant differences (p<.01) persisted after adjusting for severity level. Although differences were smaller, academic hospitals had greater lab tests per case (12.1 vs. 8.1 tests, 49.4% higher) and day (4.3 vs. 3.6 tests, 19.4% higher) for vaginal delivery hospitalizations. Laboratory RIW per case was also significantly (p<.01) higher at academic hospitals (3.4 vs. 2.8 RIW, 21.4% higher). Laboratory RIW per day did not differ significantly. Significant differences remained for the high and moderate severity vaginal delivery groups. Conclusion Academic hospitals have greater laboratory test utilization for obstetrics patients. This difference appears to be largely due to a longer mean length of stay as well as use of tests with higher RIW.