This study was conducted to examine the legitimacy of Barthel Index (BI) scores and subset of Functional Independence Measure (FIM) scores obtained by interview from patients hospitalized after stroke. This study included 82 patients with stroke. Interviews by a trained study coordinator were conducted to obtain BI and FIM subset (transfer, locomotion, feeding) scores from patients or a knowledgeable proxy. In addition, therapists' observational FIM scores on subset items recorded in the medical record were retrieved. The reliability, responsiveness, and validity of the BI and FIM subset were examined using Cronbach's alpha, effect size calculations, Wilcoxon tests, Spearman (r(S)) correlations, and regression analysis. Statistical analysis indicated that the post-stroke interview BI (.952) and FIM subset (.939) scores had excellent internal consistency. Large effect sizes and Wilcoxon test results between the prestroke and poststroke interview scores for the BI and FIM subset (z, -3.739 to -6.168) indicated that these 2 instruments were responsive to changes in patients' physical function status that accompanied stroke. Excellent correlations were found between BI and FIM interview scores poststroke (r(s), .913 to .971). The FIM subset interview scores and therapists' scores showed correlations that were moderate to good (r(s), .508 to .754). Length of stay correlated significantly with both the interview BI score (r(s), -.604) and the interview FIM subset score (r(s), -.583). Length of stay was correlated also with the National Institutes of Health Stroke Scale scores (r(s), .484). The regression analysis depicted the BI interview scores as the best predictor of the length of stay. Results provide support for the use of functional scores obtained by interview from hospitalized stroke patients. Both the BI and the FIM subset examined in this study are legitimate for this purpose.