Trunk control in children with cerebral palsy : a reliability study of the Trunk Impairment Scale

Abstract

Background and objective. Standardized scales are useful for treatment planning and evaluation. The purpose of this study was to examine the reliability of the Trunk Impairment Scale (TIS) for children with cerebral palsy (CP). Design. This was an intra- and inter-observer reliability study. Methods. Video recordings of 25 children, 20 with CP and 5 with no motor impairment, in the age group 5–12 years of age, were analyzed by three observers on two occasions. Intraclass correlation coefficients (ICC [1,1] and [3,1]) with 95% confidence intervals, within-subject standard deviation, kappa values or percent agreement, and Bland Altman Plots were calculated. Results. The relative reliability (intra- and inter-observer reliability) was very high for the total score and subscale score of TIS: ICC [1,1] and [3,1] varied between .96 and 1.00. Kappa values for the items ranged from .45 to 1.00. The absolute reliability values for the parameters are reported. The Bland Altman analysis showed consistency of scores. Limitations. The study was limited to children aged 5–12 years. Moreover, the observers were not randomly selected, but selected on the basis of varying experience in physiotherapy. Conclusion. This study indicates that TIS is a simple and reliable measure of trunk performance for children with CP.