Psychometric Properties of Functional Balance Assessment in Children With Cerebral Palsy

Background. Children with cerebral palsy often suffer from a lack of balance compared with typically developing children. Because balance capacity is relevant to functional activities, reliable and valid functional balance measures are crucial for the pediatric clinical setting. Objective. This study examined the reliability and validity of 3 functional balance measures. Methods. Thirty children aged 60 to 142 months with Gross Motor Function Classification System (GMFCS) levels of I to IV were recruited. For test-retest reliability, the same physical therapist administered the Functional Reach Test (FRT), Berg Balance Scale (BBS), and Timed Up and Go (TUG) twice. For interrater reliability, the testing processes were video recorded and later scored by another therapist. For convergent validity, children with cerebral palsy received the Gross Motor Function Measures (GMFM), walking speed, and 10-second sit-to-stand test within 1 week and the results evaluated. Results. The 3 functional balance measures had excellent test-retest reliability (intraclass correlation coefficient [ICC] >0.95) and interrater reliability (ICC = 0.98-1.00). With regard to convergent validity, the BBS and the TUG were highly correlated with GMFM total score, walking speed, and the 10-second sit-to-stand test. The discriminate validity indicates that the FRT can distinguish children with cerebral palsy with different GMFCS levels, whereas the BBS total score and TUG failed to distinguish between children with cerebral palsy with GMFCS levels of I and II. Conclusion. The 3 functional balance measures are simple, valid, and reliable for examining children with cerebral palsy and are thus suitable for clinical practice.