title: Response rates for providing a blood specimen for HIV testing in a population-based survey of young adults in Zimbabwe.
abstract: BACKGROUND
  To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS).
  
  
  METHODS
  Chi-square analysis of weighted data to compare demographic and behavioral data of persons interviewed who provided specimens for anonymous testing with those who did not. Prevalence estimation to determine the impact if persons not providing specimens had higher prevalence rates than those who did.
  
  
  RESULTS
  Comparing those who provided specimens with those who did not, there was no significant difference by age, residence, education, marital status, perceived risk, sexual experience or number of sex partners for women. A significant difference by sexual experience was found for men. Prevalence estimates did not change substantially when prevalence was assumed to be two times higher for persons not providing specimens.
  
  
  CONCLUSIONS
  When comparing persons who provided specimens for HIV testing with those who did not, few significant differences were found. If those who did not provide specimens had prevalence rates twice that of those who did, overall prevalence would not be substantially affected. Refusal to provide blood specimens does not appear to have contributed to an underestimation of HIV prevalence.
authors.affiliation: Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD and TB Prevention, Centers for Disease Control and Prevention, Atlanta, USA. aom5@cdc.gov
authors.forename: A D
authors.initials: AD
authors.lastname: McNaghten
authors.forename: Joan M
authors.initials: JM
authors.lastname: Herold
authors.forename: Hazel M
authors.initials: HM
authors.lastname: Dube
authors.forename: Michael E
authors.initials: ME
authors.lastname: St Louis
mesh_terms: D015492:AIDS Serodiagnosis / Q000706:statistics & numerical data*; D000328:Adult; D000367:Age Factors; D035841:Behavioral Research; D004196:Disease Outbreaks; D004522:Educational Status; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology*; D015528:HIV Seroprevalence; D015497:HIV-1 / Q000302:isolation & purification; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D010342:Patient Acceptance of Health Care / Q000706:statistics & numerical data*; D045808:Refusal to Participate / Q000706:statistics & numerical data*; D012424:Rural Population; D012737:Sex Factors; D014505:Urban Population; D015030:Zimbabwe / Q000453:epidemiology