Table.

Characteristics of EDs.^*

Characteristics	Responders, n=77 (80%)		2007 NEDI-USA, n=4,874
Median annual visit volume (interquartile range)	21,024 (7,884–37,668)		18,903 (7,812–35,252)
Hospital type
Teaching hospital	8	4–11	6
Trauma center (Level I–II)†	13	9–17	10
Critical access hospital	26	21–32	26
Urban influence code
Urban	57	51–63	58
Close to urban	24	19–29	23
Rural (large town)	7	4–10	6
Rural (small town)	12	8–16	12
US region
Northeast	13	9–17	14
South	28	23–34	29
Midwest	41	35–47	38
West	18	13–23	19
Uninsured patients >25%‡	34	29–39	18
Crowded by CDC criteria§	46	40–52	45
ED social worker available	76	71–81	NA

NA, Not available.

^*Data are percentage with 95% confidence interval unless otherwise indicated. NEDI-USA includes all US EDs in operation. Critical access hospital, Medicare designation as being a “necessary provider” of health care services and location greater than 35 miles from nearest hospital; urban influence code, a county-based measure of urban-rural status from the US Department of Agriculture, 2003.

^†Trauma center data are from the Trauma Information Exchange Program (TIEP), American Trauma Society, 2009.

^‡According to the ED director. National data are from the National Hospital Ambulatory Medical Care Survey (NHAMCS) 2004.¹⁰

^§Presence of at least 1 of the 3 following criteria, as reported by the ED director: average waiting time of 1 hour or greater, left without being seen rate of 3% or greater, or any annual time on ambulance diversion. National data are from NHAMCS 2004.¹⁰