Operational testing programs employing item response theory (IRT) applications benefit from of the property of item parameter invariance whereby item parameter estimates obtained from one sample can be applied to other samples (when the underlying assumptions are satisfied). In theory, this feature allows for applications such as computer-adaptive…

Scores are the most visible and widely used products of a testing program. The choice of score scale has implications for test specifications, equating, and test reliability and validity, as well as for test interpretation. At the same time, the score scale should be viewed as infrastructure likely to require repair at some point. In this report…