Normative data from the standardization of Raven's Standard Progressive Matrices in Kuwait in an international context

A probability sample (N = 6,594) of Kuwaiti school students aged 8-15 years responded to the Raven Standard Progressive Matrices (Raven, 1958). The test was administered, untimed, in group sessions. In this paper, the smoothed summary age norms for Kuwait (which will themselves be of interest to many psychologists and others working in Kuwait and neighboring countries) are first compared with what have become the standard international reference data for such work, namely the 1979 British norms, and thereafter with data collected in a wide range of cultures. It emerged that, at any point in time, the norms were remarkably stable across cultures, but have changed dramatically over time. These findings show that, while as yet unidentified features of the environment have a dramatic effect on scores, aspects of the environment that many would have expected to have a significant effect (such as differences in calligraphy) are much less important than might have been thought.