Validity and Reliability of the 4 Meter Walk Test in Parkinson Disease

Purpose: The purpose of this study was to assess the validity and reliability of the 4-meter walk test (4MWT) in people with Parkinson disease (PD). Method: Gait velocity was measured in 25 people with PD using a computerized walkway, 10-meter walk test (10MWT), and 4-meter walk test (4MWT) under three conditions: comfortable walking speed (CWS), fast walking speed (FWS), dual task (DT). Video recording was used to assess intrarater and interrater reliability of the 4MWT. Pearson’s correlation assessed validity and the intra-class correlation coefficient (ICC (2,1)) assessed intrarater and interrater reliability. Results: There was a significant correlation between the computerized walkway and the 4MWT for all conditions, CWS (r = 0.87, p < 0.001), FWS (r = .67, p = 0.002), and DT (r = .78, p < 0.001). There was significant correlation between the 10MWT and the 4MWT for all conditions, CWS (r = 0.80, p < 0.001), FWS (r = .66, p < 0.001), and DT (r = .50, p = 0.013). All reliability tests were significant at p < 0.001. Intrarater reliability values were very high for CWS (ICC (2,1) = 0.91, [.73-.97]), FWS (ICC (2,1) = 0.99, [0.98-0.99]), and DT (ICC (2,1) = 0.96, [ 0.88-0.98]). Interrater reliability values were high for CWS (ICC (2,1) = 0.90, [0.73-0.96]), FWS (ICC (2,1) = 0.99, [0.98-0.99]), and DT (ICC (2,1) = 0.95, [0.87-0.98]). Conclusion: The 4MWT is a valid and reliable tool to measure gait velocity in individuals with PD.