title: A systematic review of the application of spatial analysis in pharmacoepidemiologic research.
abstract: OBJECTIVE
  Although current reviews of the use of spatial analysis in general epidemiologic research illustrate an important and well-established role in exploring and predicting health, its application has not been reviewed in the subspecialty field of pharmacoepidemiology.
  
  
  METHODS
  We systematically reviewed the scientific literature to assess to what extent spatial analysis has been applied in pharmacoepidemiologic research and explored its potential added value.
  
  
  RESULTS
  A systematic search in PubMed and Embase/MEDLINE yielded 823 potentially relevant articles; 45 articles met our criteria for review. The studies were reviewed on study objective, applied spatial methods and units of analysis, and author-reported added value of the geographic approach used. Of the 45 included studies, 34 (76%) reported a geographic research objective. Comparative spatial methods were most often used (n = 25; 56%). Eleven studies used spatial statistics (32%); cluster analysis (n = 5) and aggregate data analysis (n = 4) being most common. Mapping was done in 15 studies (33%). The most common added value reported was to aid the planning of health policies and interventions (n = 24; 53%). A minority of pharmacoepidemiologic studies used a geographic approach and the applied methods were less advanced compared with the broader field of epidemiology.
  
  
  CONCLUSIONS
  Further advancements are needed to incorporate currently available spatial techniques to impact health care planning.
authors.affiliation: Unit of PharmacoEpidemiology & PharmacoEconomics (PE(2)), Department of Pharmacy, University of Groningen, The Netherlands. a.dijkstra@rug.nl
authors.forename: Aletta
authors.initials: A
authors.lastname: Dijkstra
authors.forename: Eelko
authors.initials: E
authors.lastname: Hak
authors.forename: Fanny
authors.initials: F
authors.lastname: Janssen
mesh_terms: D006801:Humans; D009426:Netherlands; D017891:Pharmacoepidemiology; D012106:Research; D062206:Spatial Analysis
keywords: Geography; Pharmacoepidemiology; Spatial analysis; Systematic review