Examines limitations of standard scores of achievement tests used in diagnosing learning disabilities. Consideration of these limitations is important in deciding whether a marked discrepancy exists between ability and achievement. Recommends use of developmental standard scores over status standard scores. (Author/ABB)

This document describes the theory and practice of testing; illuminates competing interests in a balanced fashion; and helps those who make decisions with tests or about testing to reach better-informed judgments. Part 1, the report of the Committee, presents a wide-ranging discussion of testing issues. The text has been kept largely free of the…

Classical test theory, item response theory, and generalizability theory all treat the abilities to be measured as continuous variables, and the items of a test as independent probes of underlying continua. These models are well-suited to measuring the broad, diffuse traits of traditional differential psychology, but not for measuring the outcomes…