affect the validity of inferences based on scores from NAEP and other large-scale assessments. While research has shed some light on the ways accommodations function and on some aspects of their effects on test performance, in the committee’s view, a central component of validity has been missing from much of this research. Without a well articulated validation argument that explicitly specifies the claims and intended inferences that underlie NAEP and other assessments, and that also explicitly specifies possible counterclaims and competing inferences, research into the effects of accommodations on assessments of students with disabilities and English language learners is likely to consist largely of a series of loosely connected studies that investigate various accommodations, more or less at random. An approach and a framework for articulating a logical validation argument for an assessment is discussed in the next chapter.