The gender gap in mathematics performance disappears if school competitions are held with a multiround rather than single-round format, U.S. researchers say. A study at Brigham Young University found the long-held belief that boys are better at math than girls disappears if competitions extend beyond a single round, suggesting the gender gap is simply a product of first-round nerves. Most school math contests are one-shot events where girls underperform relative to their male classmates, they said, but when 24 local elementary schools changed the format to go across five different rounds, girls performed as well or better than boys for the rest of the contest. "It's really encouraging that seemingly large gaps disappear just by keeping them in the game longer," BYU economics professor Joe Price said. Boys seem to have the edge when it's the first round of a competitive setting, Price said. "We don't know if it's boys getting excited and over-performing or if it's girls being too uncomfortable with the situation," Price said. It's only in a competitive setting that the gender gap seems to appear, said BYU math professor Jessica Purcell, who was not involved with the study. "In mathematical settings without time pressure or competition, such as classes I have taught or classes I have taken, males and females seem to do equally well," Purcell said.