Contemporary conceptualization of measurement validity

While the concept of measurement validity may appear straightforward, this concept can instead be deceptively complex. Over the last century, the conceptualization of validity has changed substantially. This conceptualization has evolved from a view of different types of validity to a unitary concept with multiple sources of evidence, which includes reliability. Validity and reliability were originally viewed as properties of a measurement instrument itself, although the contemporary conception of validity has come to view validity as a more nuanced reflection of how scores from a measurement instrument, in a specific group of individuals at a specific time, are interpreted and used for a particular purpose. This chapter also discusses ongoing misunderstandings and confusion in the literature, and the importance of reporting contemporary validity in helping researchers demonstrate their up-to-date knowledge to peer reviewers, grant reviewers, and research report readers.