Sex-related differences in spatial ability: more evidence for convergence.

Sex-related differences in spatial ability, favoring males, have frequently been reported in the literature. Recent analyses, however, have found indications of a convergence in the scores of men and women on spatial tests over the years. This research examined the evidence for such a secular trend in a German population using data of 18 samples that had completed the Cube Perspectives Test, a measure of spatial visualization ability. The largest effect size (d = .77) was found for a sample tested in 1978, the smallest difference (d = .38) was observed for a sample tested in 1987. There was a clear trend narrowing the sex-related differences; the correlation between the recency of the data and the respective d-value was -.926. The convergence of the scores of men and women proved to be stronger than in the previous studies.