ABSTRACT
The applied practice of measure validation has lagged behind recommendations for best practice from methodologists and professional organizations. Generally, this situation has been described in terms of both the risk that measures might be misused, leading to unfounded decisions or unfair consequences, and the risk that measures may fail to capture what was intended, muddying the waters with misleading research results. In this chapter, we take a different approach and discuss the shortfall of measure validation in mathematics education research in terms of a missed opportunity. Rather than framing validation studies as a burdensome requirement, we suggest using validation as a research methodology, that is, a way to systematically advance knowledge not just about a specific measure, but also about the broader theory to which the measure relates. We discuss two cases of validation studies, one proving that the intended use was justified and the other not, and we describe the benefits to theory that accrued in both. We argue that measure design and measure validation should become more common in mathematics education research given these benefits.
