Investigation of the validity and reliability of the 3-meter backward walk test in high functional level adults with lower limb amputation

Abstract

Background: Backward walk training has an important place in the rehabilitation programs of lower extremity amputees. Objective: This study aimed to investigate the test-retest validity and reliability of the 3-meter backward walk test (3MBWT), minimal detectable change, and the cutoff time in high functional level adults with lower limb amputations (LLAs). Adults with LLA (n = 30) and healthy adults (n = 29) were included in the study. Study design: This is a randomized cross-sectional study. Methods: The Modified Fall Efficacy Score, Rivermead Mobility Index, and Timed Up and Go test with the 3MBWT were used to evaluate the concurrent validity of the test. The second evaluation (retest) was performed by the same physiotherapist 1 week following the first evaluation (test). The validity was assessed by correlating the 3MBWT times with the scores of other measures and by comparing the 3MBWT times between adults with LLA and healthy adults. Results: Test-retest reliability of the 3MBWT was excellent. The intraclass correlation coefficient for the 3MBWT was 0.950. The standard error of measurement and minimal detectable change values were 0.38 and 0.53, respectively. A moderate correlation was found between the 3MBWT, Modified Fall Efficacy Score, Timed Up and Go test, and Rivermead Mobility Index (p < 0.001). Significant differences in the 3MBWT times were found between adults with LLA and healthy controls (p < 0.001). The cutoff time of 3.11 s discriminates healthy adults from high functional level adults with LLA. Conclusions: The 3MBWT was determined to be valid, reliable, and easy-to-apply tool in high functional level adults with LLA. This assessment is a useful and practical measurement for dynamic balance in high functional level adults with LLA.