Research has found that grades are the most valid instruments for predicting educational success. Why grades have better predictive validity than, for example, standardized tests is not yet fully understood. One possible explanation is that grades reflect not only subject-specific knowledge and skills but also individual differences in other…

The concept of validity, as described in the literature, has changed over time to become a broad and rather complex issue. The purpose of this paper is to investigate if practice has followed theory, or if there is a gap between validity in theory and validity in practice. It compares the theoretical development of the concept of validity with the…

A common problem in predictive validity studies in the educational and psychological fields, e.g. in educational and employment selection, is restriction in range of the predictor variables. There are several methods for correcting correlations for restriction of range. The aim of this paper was to examine the usefulness of two approaches to…

This article reviews ten predictive validity studies of the Swedish Scholastic Assessment Test (SweSAT). A primary result is that the predictive validity of the SweSAT seems to be highly dependent upon the study programme being examined; that is, the predictive validity is better at some programmes than others. When compared with the…

A longitudinal study was designed to develop and evaluate a screening instrument of developmental delay based on parental assessment of 18-month-old children. The reliability and validity of a parental screening instrument based on the Griffiths Mental Developmental Scale was investigated with a sample of 2,783 Swedish children out of a population…