Improving population representation through geographic health information systems: mapping the MURDOCK study.

Journal Article (Journal Article)

This paper highlights methods for using geospatial analysis to assess, enhance, and improve recruitment efforts to ensure representativeness in study populations. We apply these methods to the Measurement to Understand Reclassification of Disease of Cabarrus/Kannapolis (MURDOCK) study, a longitudinal population health study focused on the city of Kannapolis and Cabarrus County, NC. Although efforts have been made to recruit a participant registry that is representative of the 18 ZIP code catchment region inclusive of Cabarrus County and Kannapolis, bias in such recruitment is inevitable. Participants in the MURDOCK study are geospatially referenced at entry, providing information that can be used to monitor and guide recruitment efforts. MURDOCK participant population representativeness was assessed using chi-squared tests to compare the MURDOCK population with 2010 Census data, relative to both the entire 18 ZIP code catchment area and for individual Census tracts. A logistic regression model was fit to characterize Census tracts with low recruitment, defined by fewer than 56 participants from that tract. The distance to the site at which participants enrolled was calculated, and median distance to enrollment site was used in the logistic regression. Tracts with low recruitment rates contained higher minority and younger populations, suggesting specific strategies for improving recruitment in these areas. Areal units farther away from enrollment sites were also not well-sampled, despite being in the specified study area, indicating that distance traveled to enrollment may be a barrier. These results have implications for targeting recruitment efforts and representative samples more generally, including in other population-based studies.

Full Text

Duke Authors

Cited Authors

  • Strauss, BW; Valentiner, EM; Bhattacharya, S; Smerek, MM; Dunham, AA; Newby, LK; Miranda, ML

Published Date

  • 2014

Published In

Volume / Issue

  • 6 / 4

Start / End Page

  • 402 - 412

PubMed ID

  • 25075257

Pubmed Central ID

  • 25075257

International Standard Serial Number (ISSN)

  • 1943-8141


  • eng

Conference Location

  • United States