The cornerstone of evidence-centered assessment design (ECD) is an evidentiary argument that requires that each target of measurement (e.g., learning goal) for an assessment be expressed as a "claim" to be made about an examinee that is relevant to the specific purpose and audience(s) for the assessment. The "observable evidence" required to…

Evidence-centered assessment design (ECD) explicates a transparent evidentiary argument to warrant the inferences we make from student test performance. This article describes how the vehicles for gathering student evidence--task models and test specifications--are developed. Task models, which are the basis for item development, flow directly…

In many large-scale assessment programs, achievement level descriptors (ALDs) provide a critical role in communicating what scores on the assessment mean and in interpreting what examinees know and are able to do based on their test performance. Based on their test performance, examinees are often classified into performance categories. The…