Reliability and validity of disability questions for US Census 2000

We investigated the validity and proxy reliability of 7 new disability questions from the 2000 US census ("Census 2000"). A total of 131 people with disabilities and their proxies from St Louis, Mo, and Massachusetts were interviewed, and responses were compared for concordance. Responses also were compared with responses to questions from the Behavioral Risk Factor Surveillance System (BRFSS) and the Activities of Daily Living (ADL) instrument. Overall, proxies reported more impairment than did people with disabilities, and agreement was low (kappa = 0.24-0.55). Concordance was moderate between the census questions and their BRFSS and ADL counterparts. The Census 2000 questions may not provide an accurate profile of disability in America.