Clinical research is one of the most important examples of the vitality of trust in biomedical research. As defined by NIH, clinical research is human subjects research, including:

• Patient-oriented research — research conducted with human subjects (or on material of human origin such as tissues, specimens, and cognitive phenomena) for which an investigator directly interacts with human subjects
• Epidemiological and behavioral studies
• Outcomes research and health services research

A clinical trial is a research study in which one or more human subjects are prospectively assigned to one or more interventions (which may include placebo or other control) to evaluate the effects of those interventions on health-related biomedical or behavioral outcomes. A Phase III clinical trial is a study to determine efficacy of the biomedical or behavioral intervention in large groups of people (from several hundred to several thousand) by comparing the intervention to other standards or experimental interventions as well as to monitor adverse effects, and to collect information that will allow the interventions to be used safely.

In 1993, medical science took a huge leap forward when Congress made what had been NIH policy to include women and minorities in clinical research into Public Law, through a section within the 1993 NIH Revitalization Act. By this policy:

• NIH ensures that women and minorities are included in all human subject research.
• Phase III clinical trials include women and minorities in numbers adequate to allow for valid analyses of differences in intervention effect.
• Cost is not allowed as an acceptable reason for excluding these groups.
• NIH initiates programs and support for outreach efforts to recruit and retain women and minorities and their subpopulations as volunteers in clinical studies.

ORWH helps the research community understand the scientific reasoning that underpins the NIH Inclusion Policy and focuses on the importance of providing data that can inform both the research community and potential volunteer communities of the trends and shifts in including certain populations in clinical trials.

Since 1993, women's participation in NIH-funded clinical trials has grown. According to the most recent NIH biennial report (Monitoring Adherence to the NIH Policy on the Inclusion of Women and Minorities as Subjects in Clinical Research; Comprehensive Report: Tracking of Clinical Research), in FY 2014, females comprised 57.2 percent of enrollment in NIH-defined clinical research. Females also comprised 60 percent of enrollment in NIH-defined Phase III clinical trials.

Federal Partners Involved in Clinical Trials Initiatives

ORWH works closely with other government agencies in its efforts to promote participation from women and other underrepresented groups in clinical research.

• The U.S. Food and Drug Administration Office of Women's Health, established by Congress, supports initiatives to increase women's participation in clinical trials and funds research to collect these data.
• For decades, the HHS Office on Women's Health (OWH) has worked to support the inclusion of women in clinical trials. In 1985, the Public Health Service Task Force on Women's Health identified women's health research as a national priority. The Task Force was the precursor of the HHS Coordinating Committee on Women's Health, which is chaired by the OWH Director.
• The NIH's National Heart, Lung, and Blood Institute oversees the Women's Health Initiative (WHI) , launched a year after ORWH was established in 1990. The WHI, one of the largest studies of postmenopausal women's health ever conducted, enrolled more than 160,000 women and has been extended through 2020.
• Women in Clinical Trials
  The FDA presents information about women's participation in clinical trials, including where to learn about ongoing research and 15 things to ask before joining a clinical trial.