title: Proband race/ethnicity affects pedigree completion rate in a genetic study of ischemic stroke.
abstract: BACKGROUND
  A recent meta-analysis suggested that racial/ethnic status is not a major determinant of willingness to participate in observational studies or treatment trials. However, little is known about the predictors of enrollment in family-based observational genetic studies. We tested the hypothesis that proband race/ethnicity is a significant predictor of enrolling a pedigree.
  
  
  METHODS
  Univariable and multivariable logistic regression modeling was used to determine proband characteristics that predict DNA donation from both members of an affected sibling pair. A total of 619 adult male and female probands with first-time or recurrent ischemic stroke and a positive sibling history of stroke enrolled across 53 hospitals and clinics in the United States and Canada into the Siblings with Ischemic Stroke Study, a family-based prospective genomics study.
  
  
  RESULTS
  In univariable analysis, probands with siblings who agreed to a blood draw for DNA analyses were more likely to be male and less likely to be nonwhite. In multivariable analysis, only race/ethnicity was significantly associated with likelihood of a proband's having a sibling who agreed to a blood draw.
  
  
  CONCLUSIONS
  Contrary to observational studies that are not family based, the willingness of family members to participate in observational genetics studies may be influenced by race/ethnicity. This result reinforces the need for improving methods for recruiting diverse populations into genetic studies of stroke.
authors.affiliation: Department of Neurology, University of Cincinnati, Cincinnati, Ohio, USA.
authors.forename: Brett M
authors.initials: BM
authors.lastname: Kissela
authors.forename: Thomas G
authors.initials: TG
authors.lastname: Brott
authors.forename: Robert D
authors.initials: RD
authors.lastname: Brown
authors.forename: Scott L
authors.initials: SL
authors.lastname: Silliman
authors.forename: W Mark
authors.initials: WM
authors.lastname: Brown
authors.forename: Stephen S
authors.initials: SS
authors.lastname: Rich
authors.forename: James F
authors.initials: JF
authors.lastname: Meschia