title: Routine health insurance data for scientific research: potential and limitations of the Agis Health Database.
abstract: OBJECTIVE
  Observational studies performed within routine health care databases have the advantage of their large size and, when the aim is to assess the effect of interventions, can offer a completion to randomized controlled trials with usually small samples from experimental situations. Institutional Health Insurance Databases (HIDs) are attractive for research because of their large size, their longitudinal perspective, and their practice-based information. As they are based on financial reimbursement, the information is generally reliable.
  
  
  METHODS
  The database of one of the major insurance companies in the Netherlands, the Agis Health Database (AHD), is described in detail. Whether the AHD data sets meet the specific requirements to conduct several types of clinical studies is discussed according to the classification of the four different types of clinical research; that is, diagnostic, etiologic, prognostic, and intervention research. The potential of the AHD for these various types of research is illustrated using examples of studies recently conducted in the AHD.
  
  
  CONCLUSIONS
  HIDs such as the AHD offer large potential for several types of clinical research, in particular etiologic and intervention studies, but at present the lack of detailed clinical information is an important limitation.
authors.affiliation: Julius Centre for Health Sciences and Primary Care, University Medical Center Utrecht, 3508 GA Utrecht, The Netherlands. h.m.smeets@umcutrecht.nl
authors.forename: Hugo M
authors.initials: HM
authors.lastname: Smeets
authors.forename: Niek J
authors.initials: NJ
authors.lastname: de Wit
authors.forename: Arno W
authors.initials: AW
authors.lastname: Hoes
mesh_terms: D035843:Biomedical Research; D003219:Confidentiality; D003625:Data Collection / Q000592:standards* / Q000706:statistics & numerical data; D016208:Databases, Factual / Q000592:standards*; D006801:Humans; D007348:Insurance, Health / Q000592:standards*; D009426:Netherlands