Gait Deviation Index Correlates With Daily Step Activity in Children With Cerebral Palsy

Abstract Objectives To examine the association between the Gait Deviation Index (GDI), a multivariate measure of overall gait impairment, and measures of both community walking performance and walking capacity within the clinic setting in ambulatory children with cerebral palsy. Design Cross-sectional study. Setting Gait analysis, 6-minute walk test (6MWT), and self-selected walking speed (WS) were conducted in laboratory and clinic settings. Activity monitoring was done in participants' community environment. Participants Children with cerebral palsy (N=55; age range, 6–18y) with Gross Motor Function Classification System levels I to III. Interventions Not applicable. Main Outcome Measures The GDI was derived from gait analysis data as a measure of overall gait impairment; an activity monitor was used to capture community walking performance, and the 6MWT and WS were the clinic-based measures of walking capacity. Results Fifty-five children had a median GDI of 78.86 (range, 53.07–105.34). A moderate association was found between the GDI and daily step count (Spearman ρ=.58; 95% confidence interval [CI], .37–.74; P