Comparison of the six-minute walk test performed over a 15 and 30 m course by children with cerebral palsy

Background The aim of this study was to compare performance on the six-minute walk test (6MWT) performed over 15 m and 30 m courses by children and youths with cerebral palsy (CP). Methods Children and youths with CP at Gross Motor Function Classification System levels I–IV performed the 6MWT in a straight 15 m-long corridor (first trial) and 30 m-long corridor (second trial). The intraclass correlation coefficient (ICC) and Bland-Altman plots were used to evaluate the agreement between the 6MWT results for the two corridor lengths. Results We included 82 children and youths with CP (36 girls, 46 boys), with a mean age of 11.7 years (SD 4.2, range 5–22 years). There was high agreement between the results of the two 6MWTs: ICC 0.93 (95% confidence interval 0.76–0.97). The total walking distance was longer for the 30 m course (median 399 m, range 44–687 m) than the 15 m course (median 357 m, range 24–583 m). Conclusions We observed good agreement for the performance of the 6MWT in the 15 m and 30 m courses, although the total walking distance was greater for the 30 m course. We recommend that the same distance is used when evaluating changes in walking ability for an individual child. Both distances are appropriate when measuring endurance in children and youths with CP.