Reliability and minimal detectable change in the gait assessment and intervention tool in patients with multiple sclerosis

INTRODUCTION: Gait impairment is one of the main causes of disability in people with Multiple Sclerosis. The Gait Assessment and Intervention Tool is an observational gait scale which assesses kinematic parameters using video recordings. OBJECTIVE: To study intra and inter-rater reliability and the minimal detectable change of the Gait Assessment and Intervention Tool in subjects with Multiple Sclerosis. DESIGN: observational study. SETTING: Multiple Sclerosis Foundation. PARTICIPANTS: 35 subjects with Multiple Sclerosis were assessed (12 men, 23 women; 47.7±11 years; Expanded Disability Status Scale=4.32±1.4). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Intra and inter-rater reliability of the Gait Assessment and Intervention Tool was assessed for each limb using the intraclass correlation coefficient. Also, the minimal detectable change was calculated. RESULTS: The Intraclass Correlation Coefficient for the intra-rater reliability was found to be excellent for the total score both for the right side (.91; Confidence Interval 95% .85-.95) and the left side (.93; Confidence Interval 95% .88-.96). The intraclass correlation coefficient for the inter-rater reliability was .91 (Confidence Interval 95% .85-.95) for the right side, and .93 (Confidence Interval 95% .88-.96) for the left side. The minimal detectable change for the intra-rater reliability was 1.19 points for the right side and .77 for the left side. CONCLUSIONS: The Gait Assessment and Intervention Tool exhibits excellent intra and inter-rater reliability and a small minimal detectable change for people with Multiple Sclerosis. This article is protected by copyright. All rights reserved.