Sex differences in means and variability on the progressive matrices in university students: a meta-analysis.

A meta-analysis is presented of 22 studies of sex differences in university students of means and variances on the Progressive Matrices. The results disconfirm the frequent assertion that there is no sex difference in the mean but that males have greater variability. To the contrary, the results showed that males obtained a higher mean than females by between .22d and .33d, the equivalent of 3.3 and 5.0 IQ conventional points, respectively. In the 8 studies of the SPM for which standard deviations were available, females showed significantly greater variability (F(882,656) = 1.20, p < .02), whilst in the 10 studies of the APM there was no significant difference in variability (F(3344,5660) = 1.00, p > .05).