Performance-based tests in individuals with Parkinson's disease: Outcome scores and reliability

ObjectiveTo compare the outcome scores and reliability of performance-based tests (Timed "Up and Go," 10-Meter Walk Test at comfortable and maximal speeds, and Five Times Sit-to-Stand Test) in individuals with Parkinson's disease, considering one repetition and the mean of two and three repetitions.DesignReliability study.SettingResearch laboratory.Participants52 individuals with Parkinson's disease were included and assessed for inter-rater reliability (66.9 ± 6.2 years; 61.5% men) and 50 for test-retest reliability (67.1 ± 6.8 years; 62.5% men).Main measuresAssessments were conducted in two sessions, seven to 14 days apart, by two independent raters. Four performance-based tests were applied. ANOVA and intraclass correlation coefficient (ICC) were used (α=5%).ResultsFor all tests, the results were similar among the different outcome scores (0.269 ≤ F ≤ 0.046; 0.995 ≤ p ≤ 0.764), with high to very high test-retest reliability (0.73 ≤ ICC ≤ 0.96; p ≤ 0.001) and high to very high of inter-rater (0.84≤ ICC ≤ 0.96; p ≤ 0.001) reliabilities, except for Five Times Sit-to-Stand Test at one repetition, which inter-rater reliability was classified as moderate (ICC = 0.68; p ≤ 0.001).ConclusionFor all investigated tests, only one repetition, after familiarization, was necessary to provide consistent and reliable results for mobility assessment in individuals with Parkinson's disease.