Samenvatting

BACKGROUND: The mixing ability test (MAT) as an outcome measure of masticatory performance is largely used in studies with adults, but not yet with children. OBJECTIVE: This study aimed to test the construct validity and the test-retest reliability of the MAT in children with spastic cerebral palsy (CP) and children with typical development (TD). METHOD: The results of the MAT were correlated with tongue movements, mandible movements, relative muscle contraction and clinical observation measured with ultrasound, 3D kinematics, electromyography (EMG) and relevant items of the mastication observation and evaluation (MOE) instrument, respectively. Moreover, the between-groups effect was tested. Test-retest reliability was calculated with an intra-class correlation coefficient (ICC) and standard error of measurement (SEM). RESULTS: Twenty-one children (seven children with spastic CP and 14 children with TD) participated in this study. The MAT scores showed moderate to good correlations with some variables of the tongue movements, horizontal mandible movements and occlusion duration, relative muscle contraction of the left temporalis and all six MOE items (-0.80