McHugh, M., Van Dyke, K., McClelland M., Moss D. Improving Patient Flow and Reducing Emergency Department Crowding: A Guide for Hospitals. (Prepared by the Health Research & Educational Trust, an affiliate of the American Hospital Association, under contract 290-200-600022, Task Order No. 6). AHRQ Publication No. 11(12)-0094. Rockville, MD: Agency for Healthcare Research and Quality; October 2011.