Purpose: Personal assistance care is a Medicaid benefit in New York, but few data are available on its prevalence and contribution to home care. We examined these issues in a New York City sample by assessing older adults' reports of weekly home care hours and Medicaid billing records. Design and Methods: With help from New York City's Human Resources Administration, we identified all respondents in an ongoing population-based survey of Medicare enrollees who were receiving Medicaid-reimbursed personal assistance care in 1996. Results: Of respondents in the sample, 10.3% (185 of 1,902 alive through 1996) had Medicaid claims for personal assistance care. The mean was 46.1 hr/ week for reported hours and 40.1 hr/week for administrative claims. Accuracy of reported hours was evident in a high correlation (r = .91; p < .001) between respondent reports and authorized claims, and a consistently high and mostly constant ratio of billed to reported hours across all categories of activities of daily living disability. Implications: In this urban, low income, and mostly minority sample, older adults' reports of weekly formal care hours were valid when matched against administrative records. Respondent reports of formal care hours were valid even in complex care situations.Key Words: Home care, Long-term care, Concordance, Administrative records, Epidemiology