title: Test-retest reliability of colorectal testing questions on the Massachusetts Behavioral Risk Factor Surveillance System (BRFSS).
abstract: BACKGROUND
  Information on use of colorectal cancer tests, particularly for the purpose of population surveillance, is often obtained through self-report. The Behavioral Risk Factor Surveillance System (BRFSS) is a major source for population-based estimates and is used by health professionals, public health organizations, and researchers to identify and quantify self-reported utilization of screening procedures.
  
  
  METHODS
  We provide estimates of the reliability of responses among persons age > or = 50 to questions on the 1999 BRFSS questionnaire addressing two colorectal cancer testing procedures, fecal occult blood test (FOBT), and sigmoidoscopy or colonoscopy (endoscopy), based on responses of 868 persons who responded to a callback survey.
  
  
  RESULTS
  We found moderate reliability for questions addressing ever having an FOBT exam, (Kappa [K] = 0.55, 95% confidence interval [95% CI]: 0.49-0.61) and good reliability for questions addressing ever having an endoscopy exam (K = 0.69, 95% CI: 0.65-0.74). Questions addressing the timing of the most recent exam were only slightly less reliable (K = 0.49, 95% CI: 0.43-0.55 and K = 0.62, 95% CI: 0.57-0.67, respectively). We observed comparable reliability across levels of most demographic and risk factor characteristics for both ever having and recency of exam.
  
  
  CONCLUSIONS
  Our results suggest that colorectal cancer testing questions on the BRFSS display a reasonable level of test-retest reliability.
authors.affiliation: Boston University School of Medicine, Boston Collaborative Drug Surveillance Program, 11 Muzzey Street, Lexington, MA 02421, USA. bradbury@amgen.com
authors.forename: Brian D
authors.initials: BD
authors.lastname: Bradbury
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Brooks
authors.forename: Phyllis
authors.initials: P
authors.lastname: Brawarsky
authors.forename: Lorelei A
authors.initials: LA
authors.lastname: Mucci
mesh_terms: D017677:Age Distribution; D040343:Behavioral Risk Factor Surveillance System; D003113:Colonoscopy / Q000592:standards* / Q000639:trends; D015179:Colorectal Neoplasms / Q000453:epidemiology* / Q000517:prevention & control / Q000523:psychology*; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009780:Occult Blood; D010349:Patient Compliance; D011159:Population Surveillance; D015995:Prevalence; D011336:Probability; D015203:Reproducibility of Results; D018570:Risk Assessment; D017678:Sex Distribution; D011795:Surveys and Questionnaires; D014481:United States