Introduction

Purveyor: Agency for Healthcare Research and Quality

Years in the DataCore: 2006-2016

Years of data owned: 2006-2016

Unit of data: Hospital Discharge

Dataset website: https://www.hcup-us.ahrq.gov/db/nation/neds/nedsdbdocumentation.jsp 

Public-facing data dictionary: https://www.hcup-us.ahrq.gov/db/nation/neds/nedsdde.jsp

General description: The NEDS is the largest all-payer emergency department (ED) database in the United States, yielding national estimates of hospital-based ED visits. Unweighted, it contains data from approximately 31 million ED visits each year. Weighted, it estimates roughly 143 million ED visits. 

As a uniform, multi-state database, the NEDS promotes comparative studies of healthcare services and supports healthcare policy and research on a variety of topics, including:

  • Use of and charges for ED services
  • Medical treatment effectiveness
  • Quality of ED care
  • Impact of health policy changes
  • Access to care
  • Utilization of health services by special populations

Common Key Linking Variables

Patient:

  • HCUP NEDS record identifier (KEY_ED)

Hospital:

  • HCUP ED hospital identifier (HOSP_ED)

Geographical:

  • Region

Licensing and Access

All users of HCUP data must complete the HCUP Data Use Agreement (DUA) Training Course and sign an HCUP DUA before receipt of the data. See this website for further information: https://www.hcup-us.ahrq.gov/tech_assist/dua.jsp.

NEDS Structure

Core [2006-2016]

Every row of the Core dataset if an Emergency Department visit.

The primary key of the Core table is:

  • HCUP NEDS record identifier (KEY_ED)

Hospital [2006-2016]

Every row of the Hospital table is a hospital.

The primary key of the hospital table is:

  • HCUP ED hospital identifier (HOSP_ED)

Supplemental Emergency Department [2006-2016]

The supplemental emergency department dataset is bound to the core dataset using KEY_ED. It contains further information about the emergency visit.

Supplemental Inpatient [2006-2016]

The supplemental Inpatient dataset is bound to the core dataset using KEY_ED. It contains further information about the following inpatient stay.

DataCore Staff Errata

5/28/2019: No data errata, data exceptions or data corrections have been issued.

DataCore Purveyor Errata

5/28/2019: No data errata, data exceptions or data corrections have been implemented.

Provenance

The data from HCUP was sent in ascii files (.asc) with associated file specification files. It was found that these file specifications offered an accurate depiction of the data.

For the code used for these processes, email datacore@osumc.edu.

  1. Stata .do files provided by HCUP were used to load the .asc files into Stata. These files were then exported in tab separated value files (.tsv).
  2. The provided file specification files were used in order to create SQL tables to fit the data.
  3. A bulk copy program (BCP) was used in order to upload the .tsv into SQL.
  4. The website https://www.hcup-us.ahrq.gov/db/nation/neds/nedsdde.jsp was used to generate metadata about the dataset fields and was used to generate the data dictionary.