Sex Differences in Mathematics and Reading Achievement Are Inversely Related: Within- and Across-Nation Assessment of 10 Years of PISA Data
The two curves represent the magnitude of sex difference in mathematics (black) favoring boys and the sex difference in reading (green) favoring girls in all 33 countries that participated in all four PISA assessments (2000,2003,2006 and 2009). Grey shading indicates ±1 SEM. Within these countries boys at the 50th percentile of the distribution of boys’ scores have a 10 point advantage in mathematics over girls at the 50th percentile of the distribution of girls’ scores. There is no gap for the lowest performing students and a doubling of the average gap for the highest performing students. For students at the 50th percentile, girls reading advantage is about 37 points and increases for lower performing students and decreases for higher performing students. The relation between the two gaps within these countries is the same as found between countries (Figure 2). For percentiles with a small mathematics gap, the sex difference in reading is large. The larger the sex difference in mathematics within these countries, the smaller the reading gap.