title: Comparison of injury patient information from hospitals with records in both the national trauma data bank and the nationwide inpatient sample.
abstract: BACKGROUND
  Administrative and registry databases are useful for researchers given their availability and size, yet their limitations for specific applications remain undefined. We compared injury records from a large administrative database and the National Trauma Data Bank (NTDB) with the goal of furthering the understanding of their respective limitations.
  
  
  METHODS
  The study hospitals had submitted records to both the NTDB and the Nationwide Inpatient Sample (NIS) for patients admitted during 2002. Record inclusion criteria for comparison included nonelective admissions with a primary diagnosis of injury (excluding isolated hip fractures). Numbers of cases and variables common to both databases were compared.
  
  
  RESULTS
  Twenty-four hospitals had records both in the NTDB (24,619 records) and in the NIS (25,586 records). We found less missing cost and payer information in the NIS compared with the NTDB (0% and 0.1% vs. 30.5% and 24%, respectively), higher mean number of comorbidities per record in the NIS (0.77 vs. 0.18), and a lower crude case fatality rate in the NIS (3.5% vs. 5.2%).
  
  
  CONCLUSIONS
  The main differences between the databases reflected the different motives for data collection and the inclusion or exclusion criteria imposed by trauma registries. These differences require consideration when using either database to investigate injury-related questions.
authors.affiliation: Division of Research and Optimal Patient Care, American College of Surgeons, Chicago, Illinois, USA. phillipsbart@yahoo.com
authors.forename: Bart
authors.initials: B
authors.lastname: Phillips
authors.forename: David E
authors.initials: DE
authors.lastname: Clark
authors.forename: Avery B
authors.initials: AB
authors.lastname: Nathens
authors.forename: Mira
authors.initials: M
authors.lastname: Shiloach
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Freel
mesh_terms: D016009:Chi-Square Distribution; D016208:Databases, Factual; D006801:Humans; D011787:Quality of Health Care; D012042:Registries; D014193:Trauma Centers; D014481:United States / Q000453:epidemiology; D014947:Wounds and Injuries / Q000175:diagnosis / Q000453:epidemiology / Q000628:therapy