Search results for: Bush William S.

The purpose of this article is to offer the validity and reliability evidence for teacher science content assessments developed as part of the Diagnostic Teacher Assessments of Mathematics and Science (DTAMS) project. It was found that validity was strengthened by systematic synthesis of relevant documents, extensive use of external reviewers, and field tests with 900 teachers during assessment development process. The subsequent results from 4,400 teachers, analyzed with Rasch IRT modeling techniques, offer construct and concurrent validity evidence.