Satisfactory reliability has been found with respect to agreement on the functional status of individual children between parents and rehabilitation team members (ICC5.76–.96). Content validity, construct validity, concurrent validity (with the Peabody Developmental Motor Scales) and responsiveness to change have been confirmed. In this study, a Dutch translation of the PEDI was used. Internal consistency and inter-interviewer reliability of the Dutch version were studied. Alpha values ranged from .82 to .92, and ICCs ranged from .80 to 1.00. The reliability of scores obtained with the Dutch version of the GMTM and the PEDI was confirmed in earlier studies. For the present study, the evaluators received the same standardized training. Therefore, the reliability of the measurements in this study was not again determined.