Cross-Cultural Validation Study of the Japanese Version of the ABILOCO-Kids in Ambulatory Children With Cerebral Palsy Using Rasch Analysis.

Aims: To determine the structural validity, construct validity, cross-cultural validity, internal consistency and test-retest reliability of the Japanese version of the ABILOCO-Kids in children with cerebral palsy.

Methods

One-hundred sixteen parents of children with cerebral palsy (Gross Motor Function Classification System level I [n = 66], II [n = 32], and III [n = 18]) reported on walking ability using the Japanese version of the ABILOCO-Kids. For test-retest reliability, 23 participants were evaluated.

Results

The mean ABILOCO-Kids logit score was 2.48 (range -7.44 to 5.83). Rasch analysis and principal component analysis were used to determine the structural validity. The construct validity was confirmed on the basis of differences in the ABILOCO-Kids scores among the Gross Motor Function Classification System levels. Cronbach's α and the item-to-total correlation coefficient supported the internal consistency. The intra-class correlation coefficient was 0.96, standard error of measurement 0.56 and minimal detectable change 1.55. The cross-cultural validity analyses showed differential item functioning according to the analyses of the invariance of item difficulty and person's ability estimates.

Conclusions

The ABILOCO-Kids is a reliable and valid measure of walking ability in children with cerebral palsy in Japan. The lack of evidence on cross-cultural validity indicates we should interpret results cautiously in cases of international comparison.