title: Using administrative health care system records to recruit a community-based sample for population research.
abstract: OBJECTIVE
  Epidemiologists often seek a representative sample of particular persons from geographically bounded areas. However, it has become increasingly difficult to identify a sample frame that truly represents the underlying target population. We assessed the degree to which a clinic-based sample represents a target community.
  
  
  METHODS
  Our sample frame is from a large health care provider from the Minneapolis-Saint Paul, Minnesota, metropolitan area. We used U.S. Census data to examine the sociodemographic and geospatial distribution of the sampling frame and among those who did and did not respond.
  
  
  RESULTS
  Our study's overall response rate was 57%. The most impoverished areas of the target population were under-represented in our sample frame, but this under-representation was similar for both respondents and nonrespondents. In addition, our sampled population was slightly older compared to the target population. Using ecological-level census-derived markers of sociodemographic characteristics, members of the sample frame were similar to that of the target population except for being somewhat more highly educated. However, the distributions of available individual-level data such as race and education were different between respondents and the target population.
  
  
  CONCLUSIONS
  Although the use of health care administrative records for identifying a sampling frame that represents a target population has limitations, our findings suggest that this method had strengths. More comparisons of methods for identifying and recruiting target populations are needed.
authors.affiliation: Division of Epidemiology, University of Minnesota, Minneapolis. Electronic address: oakes007@umn.edu.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Oakes
authors.affiliation: Division of Epidemiology, University of Minnesota, Minneapolis.
authors.forename: Richard F
authors.initials: RF
authors.lastname: MacLehose
authors.affiliation: Division of Epidemiology, University of Minnesota, Minneapolis.
authors.forename: Kelsey
authors.initials: K
authors.lastname: McDonald
authors.affiliation: Division of Epidemiology, University of Minnesota, Minneapolis.
authors.forename: Bernard L
authors.initials: BL
authors.lastname: Harlow
mesh_terms: D000067575:Administrative Claims, Healthcare / Q000706:statistics & numerical data*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015982:Bias; D019352:Censuses; D005260:Female; D006801:Humans; D012959:Socioeconomic Factors; D062206:Spatial Analysis; D014481:United States; D055815:Young Adult
keywords: Methodology; Research subject recruitment; Sampling bias; Urban health