WASHINGTON - Women with advanced degrees in math, science, and engineering are more likely than men to be chosen for faculty positions and promotions - when they apply.

Moreover, women perform and are treated at least as well as male colleagues, according to a National Research Council analysis of hiring and promotions in the sciences at 89 U.S. universities released yesterday.

"Once women are in the pipeline, their opportunities seem to be equitable," said Sally Shaywitz, a learning-development professor at Yale University and cochair of the study.

The study found that women made up 17 percent of applicants to positions in science and engineering fields in 2004 and 2005 but were a quarter of those interviewed and 30 percent of those hired.

Less clear is why so few women apply for faculty jobs or promotions.

The study examined how women fared in competition with men for jobs and promotions in electrical engineering, biology, chemistry, civil engineering, math, and physics.

Researchers also assessed their performance and treatment in terms of grants won, laboratory space, publications in journals, and professional honors from 2004 through 2005.

The analysis, which took four years, found that male salaries averaged about 8 percent higher for full professors, which researchers said probably reflected the greater seniority of men. Salaries of male and female assistant and associate professors were equal.

Sen. Ron Wyden (D., Ore.) commissioned the report in 2002, when he chaired the Senate Subcommittee on Science, Technology and Space. The issue took on serious weight in 2005 when Lawrence Summers, then Harvard's president, suggested that innate differences between men and women could explain the disparity.

In 2007, according to the Washington-based Association for Women in Science, a quarter of tenured and tenure-track faculty in math, science, and engineering were women. For tenured faculty, the percentage was 12.5.

Alicia Carriquiry, a professor of statistics at Iowa State University and the primary data analyst, said that finding out why women don't pursue academic positions would take a separate study.

She speculated that biological clocks might be a factor. "The timing is exactly wrong," she said. "By the time they get tenure, they're in their 40s."