NRD Database Documentation

The Nationwide Readmissions Database (NRD) is a unique and powerful database designed to support various types of analyses of national readmission rates for all patients regardless of the expected payer for the hospital stay. The NRD includes discharges for patients with and without repeat hospital visits in a year and those who have died in the hospital. Repeat stays may or may not be related. The criteria to determine the relationship between hospital admissions is left to the analyst using the NRD. This database addresses a large gap in healthcare data - the lack of nationally representative information on hospital readmissions for all ages.

The links below provide detailed documentation for the NRD, from a high-level Overview to all the detailed specifications, restrictions, and resources necessary for researchers working and publishing with the NRD.
 
Description of NRD Files Restrictions on Use File Specifications and Load Programs Data Elements Additional Resources for Data Elements
  • HCUP Quality Control Procedures (PDF file, 460 KB; HTML)
  • HCUP Coding Practices (PDF file, 138 KB; HTML)
  • HCUP Hospital Identifiers (PDF file, 162 KB; HTML)
  ICD-10-CM/PCS Data Included in the NRD Starting With 2015 Known Data Issues HCUP Tools: Labels and Formats
  • Format Programs
    • DRG Formats Program (TXT file, 1.5 MB) Creates SAS formats to label the values of each DRG and MDC category
    • HCUP Formats Program (TXT file, 107 KB) Creates SAS formats to label the values of selected categorical data elements in HCUP files
    • HCUP Diagnosis and Procedure Groups Formats Program (TXT file, 8 KB) Creates SAS formats to label the values of HCUP Diagnosis and Procedure Groups data elements, including Clinical Classifications Software Refined (CCSR) data elements
    • ICD-9-CM Formats Program (TXT file, 910 KB) Creates SAS formats to label the values of ICD-9-CM Diagnoses and Procedures
    • ICD-10-CM Formats Program (TXT file, 12.2 MB) Creates SAS formats to label the values of ICD-10-CM Diagnoses and Procedures
    • Severity Formats Program (TXT file, 816 KB) Creates SAS formats to label the values of data elements in HCUP Severity Files
Obtaining HCUP Data

Internet Citation: NRD Database Documentation. Healthcare Cost and Utilization Project (HCUP). April 2021. Agency for Healthcare Research and Quality, Rockville, MD. www.hcup-us.ahrq.gov/db/nation/nrd/nrddbdocumentation.jsp.
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Last modified 4/14/21