Recruitment for the Women's Health Initiative, the largest study ever on issues pertaining to women's health, will close on time at the end of the month, according to government health officials.
The study, which began recruiting women in 1994, has enrolled more than 130,000 post-menopausal women nationwide and will meet its recruitment goals, says Dr. Jacques Rossouw, project officer for the National Institutes of Health.
The on-schedule close is a significant achievement because recruitment of such a large number of women, representing several ethnic groups, was expected to be difficult. Lower-than-anticipated enrollment levels had many researchers concerned only a year ago. Many of the study sites were charged with enrolling 10% to 60% of their participants from minority groups.
Attaining the desired number of participants, however, will enable researchers to address many of their research questions. For example, scientists hope to resolve the question of whether hormone replacement therapy helps prevent heart disease and whether HRT increases the risk of breast cancer. Researchers will also examine whether low-fat diets help prevent some diseases and whether calcium and vitamin D supplements prevent osteoporosis.
"We're ecstatic," Rossouw says. "I think it's going to be the first large, multi-centered trial to meet its recruitment goals on time."
The success in recruitment is a tribute to the American women who are now part of a historic study, he says. The project was conceived after a federal government report showed how infrequently women were being included in medical studies compared to men. The huge allocation of funds for the initiative, about $620 million, is designed to help bring knowledge of women's health up to that of men's.
According to Rossouw, researchers will release the first batch of data, a compilation of baseline statistics describing the participants, later this year. However, the findings on various research questions will probably not become available until 2005 or later.
Women ages 50 to 79 still interested in enrolling at one of the three Southern California sites (UCLA Medical Center, UC Irvine Medical Center and Harbor-UCLA Medical Center) can call the Women's Health Initiative at (800) 54-WOMEN.