Table 1.

Summary Statistics of Hospital Characteristics

	Year 1		Year 2		Year 3		Year 4
	Obs.	Mean	Obs.	Mean	Obs.	Mean	Obs.	Mean
Process score composite	2,528	−0.245	2,820	−0.017	2,579	0.231	2,227	0.389
Patient satisfaction composite	2,253	−0.146	2,489	0.046	2,416	0.162	2,171	0.343
Efficiency (expenditures per adjusted patient day)	2,792	1,685.6	3,085	1,700	2,906	1,804.3	2,583	1,929.7
EHR adoption (percent of functions)	2,797	0.437	3,094	0.46	2,906	0.5	2,591	0.585
Continuous control variables, 2011a
Case mix index							1,800	1.48
System market share							2,590	0.123

							Obs.	Percent
Categorical control variables, 2011a
Hospital size
0–99 beds							1,218	47.0
100–399 beds							1,060	40.9
400 +  beds							313	12.1
Teaching status
Major teaching							203	7.8
Minor teaching							522	20.2
Not teaching							1,866	72.2
System membership
Yes							1,378	53.2
No							1,213	46.8
Network membership
Yes							899	34.7
No							1,692	65.3
Ownership
Public							663	25.6
Private, nonprofit							1,656	63.9
Private, for‐profit							272	10.5
Location
Rural							1,166	45
Urban							1,425	55
Earliest stage 1 meaningful use attestation year
Never							519	20.0
2011 (cohort 1)							469	18.1
2012 (cohort 2)							972	37.5
2013 (cohort 3)							631	24.4

^aReported for hospitals that responded to the AHA IT supplement in 2011 and provided at least one outcome variable in 2011. Years 1‐4 correspond to calendar years 2009‐2012 for all outcomes and to calendar years 2008‐2011 for EHR adoption and all control variables.