Key Web Links
http://www.hcup-us.ahrq.gov/databases.jsp
Availability and description of data elements
http://www.hcup-us.ahrq.gov/db/nation/neds/nedsdbdocumentation.jsp
Detailed overview of sampling frame and methods
http://www.hcup-us.ahrq.gov/db/nation/neds/nedsdbdocumentation.jsp
click on “Introduction to the NEDS, 2007, Version 2”
Online overview of all HCUP databases
http://www.hcup-us.ahrq.gov/overviewcourse.jsp
Dataset Summary
The Nationwide Emergency Department Sample (NEDS) is the largest all-payer emergency department (ED) database that is publicly available in the United States, containing information from about 27 million ED visits at about 970 hospitals that approximate a 20-percent stratified sample of U.S. hospital-based EDs. Weights are provided to calculate national estimates pertaining to over 120 million ED visits in 2007. By stratifying on important hospital characteristics, such as geographic region, trauma center designation, urban-rural location, teaching status, and hospital ownership, the NEDS represents a microcosm of U.S. hospital-based EDs.
The NEDS describes ED visits, regardless of whether they result in admission, and is an exceptional resource for conducting research on high-profile emergent health delivery issues. Started in 2006 and continuing through the present, NEDS collects information on a variety of data elements including diagnoses and procedures, discharge status from the ED, patient demographics, payment source, total ED charges and total inpatient hospital charges, hospital organizational characteristics, and more. One of the most distinctive features of the NEDS is its large sample size, which allows for analysis across hospital types and the study of relatively uncommon disorders and procedures.
Extensive documentation and resources are available to facilitate data analysis. Access to the NEDS is open to users who complete an online training and sign a Data Use Agreement. Uses are limited to research and aggregate statistical reporting. One year of data on 1 DVD, compressed files in comma-delimited format is available for purchase from the HCUP Central Distributor for $500 per year ($75 for students).
Expert comments
The NEDS is the largest all-payer ED database that is publicly available in the United States. The NEDS has many research applications, as it contains information about geographic characteristics, hospital characteristics, patient characteristics, and the nature of visits (e.g., common reasons for ED visits, acute and chronic conditions, and injuries).
The NEDS is constructed using the HCUP State Emergency Department Databases (SEDD) and the State Inpatient Databases (SID). The SEDD capture discharge information on ED visits that do not result in an admission (i.e., treat-and-release visits and transfers to another hospital). The SID contain information on patients initially seen in the emergency room and then admitted to the same hospital.
The NEDS describes over 120 million yearly ED visits, an exceptional resource for conducting research on high-profile emergent health delivery issues. One of the most distinctive features of the NEDS is its large sample size, which allows for analysis across hospital types and the study of relatively uncommon disorders and procedures. Note that the database contains discharge-level rather than patient-level data, and there is no unique patient identifier that can serve to identify readmissions.
NEDS online documentation includes resources to assist with loading of data into SAS, SPSS, and Stata. As the NEDS files are quite large, attention needs to be paid to data management and computer memory issues.
Dataset Details
Dataset owner / manager
Agency for Healthcare Research and Quality (AHRQ), under the Healthcare Cost and Utilization Project (HCUP)
Study and sample characteristics
The NEDS is the largest all-payer ED database that is publicly available in the United States, containing information from about 27 million ED visits at about 970 hospitals that approximate a 20-percent stratified sample of U.S. hospital-based EDs. Weights are provided to calculate national estimates pertaining to over 120 million ED visits. Data are available from data year 2006 forward.
Data on sampling strategy and hospital inclusion criteria:
http://www.hcup-us.ahrq.gov/db/nation/neds/nedsdbdocumentation.jsp
Major foci
Major topics of data collection include:
· Principal and secondary ICD-9-CM diagnoses
· Principal and secondary ICD-9-CM and CPT-4 procedures
· Discharge status from the ED
· Patient demographics (e.g., age, gender, community-level income)
· Expected payer (e.g., Medicare, Medicaid, private insurance, and uninsured)
· Total ED charges (for ED visits) and total inpatient hospital charges (for those ED visits that result in admission)
· Hospital characteristics (e.g., region, trauma center indicator, urban-rural location, teaching status)
See http://www.hcup-us.ahrq.gov/db/nation/neds/nedsdbdocumentation.jsp
Specific foci
See section on availability and description of data elements at:
http://www.hcup-us.ahrq.gov/db/nation/neds/nedsdbdocumentation.jsp
Links to other datasets
The NEDS is not currently not linkable to other HCUP databases or other outside databases. The NEDS does not contain the same hospitals as the HCUP NIS, and cannot be used for state-level analyses.
Papers published
For a complete list of publications from the HCUP databases, see http://www.ahrq.gov/data/hcup/hcupref.htm. Publications may be searched by database at http://hcup-us.ahrq.gov/reports/pubsearch/pubsearch.jsp
Examples of papers published using NEDS include:
Zhao L, Lucado J, and Stocks C. Emergency Department Visits Associated with Motor Vehicle Accidents, 2006. HCUP Statistical Brief #84. January 2010. Agency for Healthcare Research and Quality, Rockville, MD. http://www.hcup-us.ahrq.gov/reports/statbriefs/sb84.pdf.
Owens PL, Russo CA, Spector W, and Mutter R. Emergency Department Visits for Injurious Falls among the Elderly, 2006. HCUP Statistical Brief #80. October 2009. Agency for Healthcare Research and Quality, Rockville, MD. http://www.hcup-us.ahrq.gov/reports/statbriefs/sb80.pdf.
Owens PL, and Mutter R. Payers of Emergency Department Care, 2006. HCUP Statistical Brief #77. July 2009. Agency for Healthcare Research and Quality, Rockville, MD. http://www.hcup-us.ahrq.gov/reports/statbriefs/sb77.pdf.
Dataset accessibility and cost
Access to the NEDS is open to users who complete an online training and sign a Data Use Agreement. Uses are limited to research and aggregate statistical reporting. One year of data on 1 DVD, compressed files in comma-delimited format is available for purchase from the HCUP Central Distributor for $500 per year ($75 for students).
http://www.hcup-us.ahrq.gov/tech_assist/centdist.jsp
SAS, Stata, and SPSS data load programs are available, as are files to assist with dataset labeling, formatting, and coding.
http://www.hcup-us.ahrq.gov/db/nation/nis/nisdbdocumentation.jsp
Help Desk
See http://www.hcup-us.ahrq.gov/tech_assist/index_abc.jsp for answers to frequently asked questions.
Additional support can obtained via
• email: hcup@ahrq.gov
• Phone (toll free): 1-866-290-HCUP
See: http://www.hcup-us.ahrq.gov/techassist.jsp for details.
Request a consultation (SGIM members only)
Members of SGIM may request a one-time consultation with an expert in this dataset, for example to explore research ideas or to troubleshoot a problem or vexing question. Please click here for guidelines and the request process