Construct Validity: A Unitary Concept for Occupational Therapy Assessment and Measurement

BackgroundIn the traditional view of validity, it is divided it into three sub-types: content, criterion-related, and construct. Validity has recently been reconceptualized as a unitary factor known as construct validity. Five sources of construct validity evidence have been specified: test content, response processes, internal structure, relationships to other variables, and consequential aspects of construct validity. They function either as general validity criteria or as standards for all assessment and measurement.PurposeThe purpose of the manuscript is to present an overview of the contemporary conceptualization of construct validity and its relevance to occupational therapy practice, education, and research.Key Issues & ImplicationsTaken together, the five components of construct validity evidence provide a way of addressing the multiple and interrelated validity questions that need to be answered in order to justify occupational therapy test score interpretation and use by practitioners. Given the context of evidence-based practice, professional standards of practice, increasing calls for accountability, and the fact that validity of a test, instrument, or scale is now seen as being a dynamic process, it is important for occupational therapists to be conversant with this contemporary view of construct validity, and the body of validity evidence related to the assessment tools used in clinical practice.