Development and validation of item sets to improve efficiency of administration of the 66‐item Gross Motor Function Measure in children with cerebral palsy

AIM: To develop an algorithmic approach to identify item sets of the 66-item version of the Gross Motor Function Measure (GMFM-66) to be administered to individual children, and to examine the validity of the algorithm for obtaining a GMFM-66 score. METHOD: An algorithmic approach was used to identify item sets of the GMFM-66 (GMFM-66-IS) using data from 95 males and 79 females with cerebral palsy (CP; mean age 14y 7mo, SD 1y 8mo, range 12y 7mo …