Validation of the relation between the type and amount of seating support provided and Level of Sitting Scale (LSS) scores for children with neuromotor disorders.

OBJECTIVES: To assess the construct validity of the Level of Sitting Scale (LSS) by examining the relationship between LSS scores and the type and amount of seating supports.
METHODS: Secondary analysis of the data for 114 children ≤18 years, with neuromotor disorders who participated in a responsiveness study of the Seated Postural Control Measure.
RESULTS: A significant inverse relationship (Spearman rho = -0.42, p < 0.05) was found between LSS scores and amount of seating support provided. Statistically significant differences were also revealed between LSS levels of sitting ability (p < 0.004) and pelvic, thigh, trunk and head seating components and type of seating system, using Kruskal-Wallis test.
CONCLUSION: This study provides evidence of construct validity for the LSS in use as a discriminative measure of sitting ability in children with neuromotor disorders. Further validation is justified. Clinically intuitive associations between sitting ability and seating interventions were confirmed.