This National Council on Measurement in Education (NCME) module is designed to help teachers understand test reliability requirements. Focus is on the reliability of scores from teacher-made achievement tests used for interpreting norm-referenced scores. Reliability, factors affecting scores, reliability estimation methods, reliability's relation…

A sample (N=37) of currently published achievement tests was surveyed as to the availability of five types of technical data: (1) item selection techniques; (2) standardization; (3) types of norms; (4) types of validating data; and (5) types of reliability data. Recommendations for publishers and cautions for test users are given. (BS)