You Can't Fatten A Hog by Weighing It – Or Can You? Evaluating an Assessment for Learning System Called ACED

The purpose of the study described in this paper was to evaluate the efficacy of an assessment for learning system named ACED (Adaptive Content with Evidence-based Diagnosis). We used an evidencecentered design approach to create an adaptive, diagnostic assessment system which includes five main models: competency, evidence, task, presentation, and assembly. We also included instructional support in the form of elaborated feedback. The key issue we examined was whether the inclusion of the feedback into the system (a) impairs the quality of the assessment (relative to validity, reliability, and efficiency), and (b) does, in fact, enhance student learning. Results from a controlled evaluation testing 268 high-school students showed that the quality of the assessment was unimpaired by the provision of feedback. Moreover, students using the ACED system showed significantly greater learning of the content compared with a control group. These findings suggest that assessments in other settings (e.g. state-mandated tests) might be augmented to support student learning with instructional feedback without jeopardizing the primary purpose of the assessment.