The aim of this article is to compare empirically measurement models from classical test theory, generalizability theory and item response theory. First the basic concepts of these measurement theories are presented. Then, using an attitude questionnaire of nine items administered to 3 600 subjects, the results of the psychometrical analyses associated with each of the theories are compared. Most of the psychometrical observations associated with a measurement theory are reproduced by the other two approaches. These results suggest that, even if these theories seem conceptually different, they lead to the same conclusions about basic psychometrical observations.