Validation of a Model of Gross Motor Function for Children With Cerebral Palsy

Abstract

Background and Purpose. Development of gross motor function in children with cerebral palsy (CP) has not been documented. The purposes of this study were to examine a model of gross motor function in children with CP and to apply the model to construct gross motor function curves for each of the 5 levels of the Gross Motor Function Classification System (GMFCS). Subjects. A stratified sample of 586 children with CP, 1 to 12 years of age, who reside in Ontario, Canada, and are known to rehabilitation centers participated. Methods. Subjects were classified using the GMFCS, and gross motor function was measured with the Gross Motor Function Measure (GMFM). Four models were examined to construct curves that described the nonlinear relationship between age and gross motor function. Results. The model in which both the limit parameter (maximum GMFM score) and the rate parameter (rate at which the maximum GMFM score is approached) vary for each GMFCS level explained 83% of the variation in GMFM scores. The predicted maximum GMFM scores differed among the 5 curves (level Iϭ96.8, level IIϭ89.3, level IIIϭ61.3, level IVϭ36.1, and level Vϭ12.9). The rate at which children at level II approached their maximum GMFM score was slower than the rates for levels I and III. The correlation between GMFCS levels and GMFM scores was Ϫ.91. Logistic regression, used to estimate the probability that children with CP are able to achieve gross motor milestones based on their GMFM total scores, suggests that distinctions between GMFCS levels are clinically meaningful. Conclusion and Discussion. Classification of children with CP based on functional abilities and limitations is predictive of gross motor function, whereas age alone is a poor predictor. Evaluation of gross motor function of children with CP by comparison with children of the same age and GMFCS level has implications for decision making and interpretation of intervention outcomes. [Palisano RJ, Hanna SE, Rosenbaum PL, et al. Validation of a model of gross motor function for children with cerebral palsy. Phys Ther. 2000;80:974 -985.]

Assessment of body composition in children with cerebral palsy: a cross‐sectional study inNorway

“…18 The Gross Motor Function Classification System (GMFCS) is used to record the severity of gross motor function impairments on a five-level scale, with children at levels I and II being able to walk without support, while children at level V are unable to walk. 19 Study participants' GMFCS level was reported by parents, and confirmed by reference to data recorded in the Cerebral Palsy Register of Norway. In accordance with the study by Gurka et al, 8 we divided the participants into two groups: GMFCS I and II, defined as children with less severe motor impairments, and GMFCS III to V, defined as children with more severe motor impairments.…”

Intermittent versus continuous physiotherapy in children with cerebral palsy

“…Studies have proved GMFM to be reliable and valid. [5][6][7] Provided an alpha level of 5%, a beta of 20%, and a minimal relevant difference of 10%, the sample size was calculated at seven participants per group based on the known variability of the test. 2 Three children, two from the I group, one from the C group, dropped out after randomization but before intervention started; one due to family circumstances, one because the parents had second thoughts about their child's participation in the I group, and one because the parents wanted to try alternative treatment.…”

Development of the Gross Motor Function Classification System for cerebral palsy

“…Nominal group and Delphi survey consensus methods were used with independent classification of 77 children by 51 therapists. 4 Using 'concurrent validity' it was possible to demonstrate that GMFM scores generally varied significantly by GMFCS level 9,10 and that the overall correlation between the measure and the classification was very high at -0.91. 9 Stability of classification levels over time has been explored using chart reviews of prospectively collected data 11 and by analyzing data on 656 children with CP classified a mean of 4.3 times at 6 or 12 month intervals.…”