Drivers of Routine Inpatient Laboratory Overuse and Preferred Stewardship Interventions Among Residents: A...

The objective of the study was to characterize residents' self-reported inpatient laboratory and imaging ordering practices, perceived drivers of routine daily testing, and preferred stewardship strategies.

We conducted an anonymous cross-sectional web-based survey of internal medicine and general surgery residents at a tertiary academic medical center. The survey assessed resident characteristics, attitudes toward routine laboratory testing, self-reported ordering practices, perceived drivers of unnecessary testing, and preferred interventions to improve ordering behavior. Responses were summarized using counts and percentages, with Wilson 95% confidence intervals calculated for key proportions. Exploratory subgroup comparisons were performed using Fisher's exact test.

Among 115 invited residents, 62 complete responses were included (53.9%). Frequent routine laboratory ordering was reported by 40 (64.5%), although most respondents disagreed with daily laboratory testing irrespective of clinical need. The most commonly perceived unnecessary tests were chemistry panels, selected by 47 (75.8%), and complete blood counts, selected by 46 (74.2%). The most cited drivers of unnecessary testing were habitual practice, reported by 39 (62.9%), limited cost awareness, reported by 36 (58.1%), and anticipated attending requests, reported by 27 (43.5%). The most endorsed strategies were brief cost awareness sessions, selected by 37 (59.7%), bundled laboratory pricing, selected by 34 (54.8%), and removing daily laboratory options from order sets, selected by 27 (43.5%). Efficiency training on laboratory and imaging ordering was perceived as beneficial by 47 (75.8%). In exploratory subgroup analyses, frequent routine laboratory ordering was more common among junior than senior residents, 29 of 36 (80.6%) versus 11 of 26 (42.3%), Fisher's exact p = 0.003, while no significant difference was observed between internal medicine and general surgery residents.

Residents perceived routine repeat inpatient laboratory testing as a low-value practice, yet many reported ordering routine tests frequently. The main perceived drivers were modifiable system and training factors, including habit, limited cost visibility, default order sets, and perceived attending expectations. These findings support the development of a resident-informed diagnostic stewardship intervention focused on practical education, cost transparency, and workflow changes.