Assessment of sign language development: the case of deaf children in the Netherlands.

In this article, we will describe the development of an assessment instrument for Sign Language of the Netherlands (SLN) for deaf children in bilingual education programs. The assessment instrument consists of nine computerized tests in which the receptive and expressive language skills of deaf children at different linguistic levels (phonology, vocabulary, morphosyntax, and narration) are assessed. We will describe how the instrument was developed and normed, and present some psychometric properties of the instrument.