Jakobsen, Thomas Linding2; Kehlet, Henrik4; Bandholm, Thomas2
1 Section of Surgery and Internal Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet2 unknown3 Department of Clinical Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet4 Department of Clinical Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet
PURPOSE: The 6-min walk test is a simple clinical outcome measure, which has been used frequently to assess functional performance in many different patient groups, including patients with total knee arthroplasty (TKA). The 6-min walk test measures the maximal distance a subject is able to walk in 6 min. The reliability is unknown in patients with TKA. Therefore, the purpose of the study was to assess the reliability of the 6-min walk test in patients with recent TKA. METHODS: Thirty-four patients with TKA performed 2 test trials the same day, separated by a 1-h seated rest. To assess reliability, intra-class correlation coefficient (ICC(2,1)), standard error of measurement (SEM), and smallest real difference (SRD) were calculated. RESULTS: The patients walked on average 14.1 m longer at the second (397.2 m) compared to the first (383.1 m) test trial. The ICC(2,1), SEM, and SRD were 0.97, 13.0, and 36.1 m, respectively. CONCLUSIONS: The intra-tester reliability of the 6-min walk test was high in patients with TKA. The thresholds of the 6-min walk test to detect a real change are acceptable in research (SEM) and clinical settings (SRD). We recommend that the longest distance walked in 2 supervised test trials should be used. LEVEL OF EVIDENCE: I.