Constructing validity arguments for test combinations

• An extension of the argument-based approach to validation.
• Approach to validating combinations of tests that lead to one decision.
• An interpretive argument is transformed to fit test combinations.
• Validity arguments mainly address claims specific for test combinations.
• Approach fosters an in-depth evaluation of the assessment program.

The argument-based approach to validation has been widely adopted in validation theory. However, this approach aims to validate the intended interpretation and use of a single test or assessment. This article proposes an extension of the argument-based approach for validation of multiple tests. This extension is illustrated with the validation of a competency assessment program (CAP). This CAP was validated in collaboration with a quality manager of an educational program. In this case study, it became apparent that this approach fosters an in-depth evaluation of the assessment program and that the approach appears suitable for validation efforts of competency assessment programs. The approach guides validation research from a more general perspective, but also guides more detailed validation efforts.