Changing conceptions of measurement validity: an update on the new standards.

This article serves as a follow up to a 1997 article in the Journal of Nursing Education, in which the author presented a historical overview of the ways in which views of measurement validity had changed during the past half century. The new American Educational Research Association, American Psychological Association, and National Council on Measurement in Education Standards for Educational and Psychological Testing, released in 1999, includes a revised conceptualization of validity. The key changes, including the elimination of the old "trinity" view of validity and the operationalization of validity as five types of evidence, are described in this article, and specific ways to obtain evidence of each type are provided. The article concludes with a brief discussion of some of the major continuing issues and challenges in validity theory and practice.