ABSTRACT
This article provides a brief introduction to the set of four articles in the special issue. To provide a foundation for the issue, key terms are defined, a brief historical overview of validity is provided, and a description of several different validation approaches used in the issue are explained. Finally, the contribution of the articles to further articulating argument-based validation approaches is discussed, along with questions for the field to consider.
Disclosure statement
No potential conflict of interest was reported by the authors.