Assessing language comprehension in motor impaired children needing AAC: validity and reliability of the Norwegian version of the receptive language test C-BiLLT.

Children with severe motor impairments who need augmentative and alternative communication (AAC) comprise a heterogeneous group with wide variability in cognitive functioning. Assessment of language comprehension will help find the best possible communication solution for each child, but there is a lack of appropriate instruments. This study investigates the reliability and validity of the Norwegian version of the spoken language comprehension test C-BiLLT (computer-based instrument for low motor language testing) - the C-BiLLT-Nor - and whether response modality influences test results.