Background: Differences in self-reported disability may be found for older black and white adults with knee osteoarthritis (OA).
Methods: This secondary analysis of data from a randomized single-blind clinical trial examined race differences in the relationship between self-reports and timed performance tests of walking. Study participants were 518 older adults (131 blacks, 387 whites), including 363 women and 155 men, with an average age of 68.6 years.
Results: Older black and white adults with radiographically documented knee OA reported equivalent functional ability and pain severity. However, both blacks' OA severity rating and tested performance were significantly worse than those of whites. Self-report and tested walking performance were significantly less correlated among black older adults than among white older adults. Analyses of potential confounding variables documented that the difference was not due to marital status, gender, education, income, body mass index, comorbidity, pain level, OA severity or general health.
Conclusions: Self-reports of OA disability were less related to tested performance for walking among black older adults. Clinicians' knowledge of black patients' underestimation of their disability has compelling potential for improving clinical treatment and enhancing diagnostic approaches to care of older adults.