Differences in test ordering between nurse practitioners and attending emergency physicians when acting as Provider in Triage

Study objectives: To compare diagnostic test ordering practices of NPs with those of physicians in the role of Provider in Triage (PIT).

Methods: This was a secondary analysis of data from a prospective RCT of waiting room diagnostic testing, where 770 patients had diagnostic studies ordered from the waiting room. The primary outcome was the number of test categories ordered by provider type. Other outcomes included total tests ordered by the end of ED stay, and time in an ED bed. We compared variables between groups using t-test and chi-square, constructed logistic regression models for individual test categories, and univariate and multivariate negative binomial models.

Results: Physicians ordered significantly more diagnostic test categories than NPs (1.75 vs. 1.54, p<0.001). By the end of their ED stay, there was no significant difference in total test categories ordered between provider type: physician 2.67 vs. NP 2.53 (p=0.08), using a nonbinomial model, incidence rate ratio (IRR) 1.07 (0.98-1.17). Patient time in an ED bed was not significantly different between physicians and NPs (NP 244min, SD=133, Physicians 248min, SD=152) difference 4min (-24.3-16.1) p=0.688.

Conclusion: NPs in the PIT role ordered slightly less diagnostic tests than attending physicians. This slight difference did not affect time spent in an ED bed. By the end of the ED stay, there was no significant difference in total test categories ordered between provider types. PIT staffing with NPs does not appear to be associated with excess test ordering or prolonged ED patient stays.