Background: The Level of Sitting Scale (LSS) is a valid and reliable classification index that categorizes sitting ability. The aim of this study is to establish the Turkish validity and reliability of the LSS in children with cerebral palsy (CP).
Methods: In total, 165 children (75 girls and 90 boys) between the ages of 4 and 18 years who were diagnosed with CP were included in the study. All children were evaluated by two independent physiotherapists for the interrater reliability analysis of the LSS and were reevaluated 1 week later by the same physiotherapist for the intrarater reliability analysis. The Gross Motor Function Classification System (GMFCS) was used for validity analysis.
Results: The intrarater reliability analyses of the LSS showed an intraclass correlation coefficient of 0.999 (ICC 95% CI [0.999-1]),and the interrater reliability analyses showed an intraclass correlation coefficient of 0.998 (ICC 95% CI [0.998-0.999]). A statistically significant, negative, and strong correlation was found between the GMFCS and the LSS (p < 0.001, r = -0.770).
Discussion: The Turkish version of the LSS in children with CP is a valid and reliable scale. The Turkish LSS can be used by researchersand clinicians in research and to determine the sitting level of children with CP.
Keywords: Cerebral palsy; children; reliability; sitting level; validity.