To Batch or Not to Batch: Test-Ordering Variability in the Emergency Department and the Impact on Care Delivery

Emergency Department (ED) patients may receive varying diagnostic workups and dispositions based on physician factors instead of solely based on presenting conditions. This study delves into the contrasting practices of batch-ordering multiple tests simultaneously versus the sequential ordering of tests based on previous results. Our analysis revealed stark differences in physician diagnostic approaches, even when working in similar environments. Findings suggest that physicians who predominantly make use of batching (“batchers”) tend to order more tests, which is associated with longer lengths of stay and increased costs. In contrast, other physicians (“non-batchers”) order fewer tests, which is associated with lower lengths of stay and costs, without any impact on primary ED outcome measures, such as the 72-hour rate of return. Thus, our results suggest an “information gain” advantage in the non-batching strategy: by ordering sequentially, non-batchers obtain the diagnostic information needed with a lower number of tests, enabling them to deliver the same quality of care more efficiently (e.g., with a lower length of stay and cost) than batchers. Finally, our study shows that the decision to batch order diagnostic tests can be optimized for each patient using a few variables, including acuity, chief complaints, and the ED volume at arrival.