The Agency for Healthcare Research and Quality (AHRQ) has released the 2011 data year of the Nationwide Emergency Department Sample (NEDS). The NEDS is the largest all-payer emergency department (ED) database in the United States and enables analyses of ED utilization patterns to support understanding and decision-making regarding this critical source of health

Constructed using records from both the HCUP State Emergency Department Databases (SEDD) and the State Inpatient Databases (SID), the 2011 NEDS contains data from nearly 30 million ED visits and encompasses all encounter data from hospital-based EDs in 30 states — approximating a 20-percent stratified sample of EDs from community hospitals. Weights are provided to calculate national estimates pertaining to the more than 131 million ED visits that took place in 2011. The NEDS provides information on "treat-and-release" ED visits, as well as ED visits in which the patient was admitted to the same hospital for further care.

Additional information about the NEDS can be found on the HCUP-US Website. The 2011 NEDS can be purchased through the HCUP Central Distributor, and select aggregated statistics can be accessed via HCUPnet.