A new study to be released today on gender equity in education concludes that a "boys crisis" in U.S. schools is a myth and that both sexes have stayed the same or improved on standardized tests in the past decade.

The report by the nonprofit American Association of University Women, which promotes education and equity for women, reviewed nearly 40 years of data on achievement from fourth grade to college and for the first time analyzed gender differences within economic and ethnic categories.

The most important conclusion is that academic success is more closely associated with family income than with gender, its authors said.

"A lot of people think it is the boys that need the help," co-author Christianne Corbett said. "The point of the report is to highlight the fact that that is not exclusively true. There is no crisis with boys. If there is a crisis, it is with African American and Hispanic students and low-income students, girls and boys."

The report is the latest and, according to the AAUW, the most comprehensive, of several issued over the past two decades by groups alleging crises -- first among girls, then boys.

Advocates for girls started making their case in the early 1990s, saying boys got more attention from teachers and were steered toward math and science more than girls, resulting in achievement gaps. More recently, advocates for boys have argued that the tide had turned and that boys were falling behind.

The AAUW report looks at many indicators of educational achievement, including dropout and disciplinary rates. It analyzes data from SAT and ACT college entrance exams and the National Assessment of Education Progress, known as the nation's report card, as well as federal statistics about college attendance, earned degrees and other measures of achievement.

Researchers concluded that:

* A literacy gap in favor of girls is not new, nor is it increasing. Over the past three decades, the reading gap favoring girls on NAEP has narrowed or stayed the same. Nine-year-old boys scored higher than ever on the reading assessment in 2004; scores for 13- and 17-year-old boys were higher or not much different from scores in the 1970s.

* A gender gap still exists favoring boys in math, especially among 17-year-olds on the NAEP.

* The percentages of students scoring at higher levels of proficiency on the NAEP are rising for both boys and girls.

* Students from lower-income families -- families with incomes of $37,000 or less -- are less likely to be proficient in math and reading. Gender differences vary significantly by race and ethnicity.

* There is virtually no gap between boys and girls entering college immediately after high school.