Self-assessment using 30-second chair stand test for patients with knee osteoarthritis – an intra- and inter-rater reliability study

Background We aimed to evaluate the intra-rater reliability in 30-second chair stand test (30CST) as a self-test, and the inter-rater reliability comparing a self-test with a physiotherapist-assessed 30CST for patients with knee osteoarthritis (KOA). The second purpose was to evaluate the classification ability of the 30CST as self-test to distinguish between reduced physical function and normal function.