An introduction to the use of evidence-centered design in test development

The purpose of this article is to describe what Evidence-Centered Design (ECD) is and to explain why and how ECD is used in the design and development of tests. The article will be most useful for readers who have some knowledge of traditional test development practices, but who are unfamiliar with ECD. The article begins with descriptions of the major characteristics of ECD, adds a brief note on the origins of ECD, and discusses the relationship of ECD to traditional test development. Next, the article lists the important advantages of using ECD with an emphasis on the validity of the inferences made about test takers on the basis of their scores. The article explains the nature and purpose of the 'layers' or stages of the ECD test design and development process: 1) domain analysis; 2) domain modeling; 3) conceptual assessment framework; 4) assessment implementation; and 5) assessment delivery. Some observations about my experience with the early application of ECD for those who plan to begin using ECD, a brief conclusion, and some recommendations for further reading end the article.