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Researchers identify measures of workflow that may help to explain and manage emergency department overcrowding

Despite growing concern about emergency department (ED) overcrowding, there are few tools available to help understand, monitor, and measure it. As a first step in addressing the problem, the Agency for Healthcare Research and Quality provided support through the Agency's Integrated Delivery System Research Network (contract 290-00-0015) for developing and refining potential measures of ED overcrowding.

A group of 74 experts from around the Nation identified 113 potential measures of ED and hospital workflow using a model that segmented the measures into three categories describing patient flow through the ED: input, throughput, and output. Ten investigators used group consensus methods to revise and consolidate the measures into a refined set of 30 measures that were then rated by all 74 experts. After further review, eight additional measures were developed and also rated by the reviewers for a total of 38 measures (15 input, 9 throughput, and 14 output).

The research team, which included Robin M. Weinick, Ph.D., of AHRQ's Office of Performance Assessment, Resources, and Technology, grouped the measures according to seven main concepts: patient demand (input), that is, volume of patients presenting to the ED for medical care; patient complexity, such as urgency and potential seriousness of the presenting complaint; ED capacity (output), ability of the ED to provide timely care for the level of patient demand according to the adequacy of physical space, equipment, personnel, and organizational system; ED workload (throughput), the demand and complexity of patient care that is undertaken by the ED within a given period; ED efficiency, the ability of the ED to provide timely, high-quality emergency care while limiting waste of equipment, supplies, and effort; hospital capacity (output); and hospital efficiency (output).

Individual measures ranged from ED ambulance patient volume and ambulance diversion episodes to ED occupancy rate, inpatient cycling time, ED boarding burden (mean number of ED patients waiting for an inpatient bed within a defined period relative to the number of staffed treatment areas), and ED volume to hospital capacity ratio. The 38 measures developed in this study show great promise for assisting in the management or prevention of ED crowding, according to lead investigator Brent R. Asplin, M.D., M.P.H., of HealthPartners Medical Group and Clinics in Minneapolis, MN, and Regions Hospital, St. Paul, MN.

More details are in "Emergency department crowding: Consensus development of potential measures," by Leif I. Solberg, M.D., Dr. Asplin, Dr. Weinick, and David J. Magid M.D., M.P.H., in the December 2003 Annals of Emergency Medicine 42(6), pp. 824-834.

Reprints (AHRQ Publication No. 04-R021) are available from AHRQ Publications Clearinghouse.

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