The School Achievement Test (SAT) assesses learning through three subtests: reading, writing and arithmetic. The goal of this study was to know which parts of the ability continuum are measured by the subtests as well as the amount of information provided in the reading and writing subtests using the Item Response Theory (IRT). The sample consisted of 1850 children. Results indicated that the writing subtest precisely measures average levels of ability and less satisfactorily low and high levels. The reading subtest revealed to have adequate discrimination for low and average levels of ability. The parts of the ability continuum which are adequately measured provide high amounts of information, indicating that reading and writing subtests are doing well.
Educational achievement; School Achievement Test; psychological evaluation; item response theory
