When 15-year-olds from different countries took the same math test, little or no difference was seen in scores between girls and boys living in cultures with few sex-based restrictions on girls.
Test scores for girls lagged the most in countries where gender inequities were most pervasive.
"The so-called gender gap in math skills seems to be at least partially correlated to environmental factors," says economist and study researcher Paola Sapienza, PhD of Northwestern University's Kellogg School of Management. "The gap doesn't exist in countries in which men and women have access to similar resources and opportunities."
Gender Gap: Nature vs. Nurture
The question of whether nature or nurture has the bigger impact on why boys seem to do better in math and girls in reading has been studied for decades.
The fact that there is little difference before the teenage years favors the idea that environment plays a bigger role than biology, Sapienza tells WebMD.
"I think the majority of researchers studying this think that it is a bit of both," she says. "But it is important to understand this. If, for example, 95% of the effect is biological, this means there probably isn't much we can do to change it from a policy standpoint."
The new research, appearing in the May 30 issue of Science, suggests that the opposite is true.
Sapienza and colleagues analyzed the scores of 276,000 teenagers living in 40 countries who took the same standardized tests designed to measure math, reading, science, and problem-solving ability.
When all the scores were combined, boys outscored girls in math by an average of 10 points, and girls outscored boys in reading by almost 33 points.
The researchers assessed cultural views regarding the roles of women and men in each of the countries by reviewing data from established surveys of gender equity.
The surveys asked questions such as "Should women work outside the home?" and "Is it more important for a man to get a college education than a woman?"
In countries with the fewest social and cultural restrictions on women -- including Iceland, Sweden, and Norway -- math scores for girls were as good as boys or better.
The biggest math score gender gap occurred in Turkey, where girls' scores lagged behind boys by 23 points. Turkey also scored among the lowest on the gender equity surveys.
The U.S. fell in the middle of the pack, with girls scoring 10 points lower on average in math than boys.
Bridging the Gender Gap
The reading advantage that has been traditionally seen among girls did not appear to be greatly influenced by culture.
In every country girls performed better than boys in reading, but the gap was widest in countries with the fewest gender inequities.
Among boys, the overall scores in math and reading were higher in the countries offering the most advantages to women and lowest in countries offering the least.
"This is important because it shows that advances for girls do not come at the expense of boys," Sapienza says.
Yale professor of physics and astronomy C. Megan Urry, PhD, tells WebMD that it is clear that cultural influences play a big role in learning. But she adds that gender is just one piece of a complex puzzle.
Urry chairs the department of physics and directs the Yale Center for Astronomy and Astrophysics.
"People make a big deal about the gender gap in mathematics, but the fact is Japanese women are better at mah than American men," she says.
This is because as a culture the Japanese place a higher value on learning math than Americans do.
The math gender gap has shrunk in the U.S. as girls have seen their opportunities in math and science grow.
"Over the last 30 years it has changed a lot, so it is pretty clear that this is more a function of attitudes than physiology," Urry says.
By Salynn Boyles
Reviewed by Louise Chang
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