Table 2. Provider productivity, efficiency, and performance measurements comparison between attendings working solo and attendings working with residents.

	ProductivityNumber of New Patients per HourMedian (IQR)Mean (SD)	EfficiencyProvider to Disposition Time (Hours)Median (IQR)Mean (SD)	Performance*Attending Performance IndexMedian (IQR)
	Total Patients Before Propensity Score Matching (N = 111,154)
Attendings Working Solo	3 (2, 4) a	2.4 (1.4, 3.6) c	0.16 (0.08, 0.36) e
	2.9 (1.6) a	2.7(1.8) c
Attendings Working with Residents	3 (2, 4)	2.7 (1.7, 3.9)	0.17 (0.09, 0.34)
	3.3 (1.9)	3.0 (2.0)
	Total Patients After Propensity Score Matching (N = 14,074)
Attendings Working Solo	3 (2, 4) b	2.4 (1.4, 3.6) d	0.16 (0.08, 0.36) f
	2.9 (1.6) b	2.7 (1.8) d
Attendings Working with Residents	3 (2, 4)	3.0 (1.9, 4.1)	0.15 (0.08, 0.27)
	3.1 (1.7)	3.2 (1.9)

a: p < 0.001 (productivity comparison between Attendings Working Solo and Attendings Working with Residents)

b: p < 0.001 (productivity comparison between Attendings Working Solo and Attendings Working with Residents) using propensity score matching.

c: p < 0.001 (efficiency comparison between Attendings Working Solo and Attendings Working with Residents)

d: p < 0.001 (efficiency comparison between Attendings Working Solo and Attendings Working with Residents) using propensity score matching.

e: p = 0.037 (performance index comparison between Attendings Working Solo and Attendings Working with Residents)

f: p < 0.001 (performance index comparison between Attendings Working Solo and Attendings Working with Residents) using propensity score matching.

* Attending Performance Index (API) refers to formula: API = (number of new patients per hour seen by a provider)/((patient acuity level determined by ESI)² x (provider to disposition time in hours)).

Abbreviations and definitions: IQR, Interquartile Range; Provider to Disposition Time, time interval between initial provider encounter to disposition (i.e., admit, discharge, transfer) in hours