Clinical Trials Have Improved on Including Women, But Still Fail to Implement the Intent of the NIH Revitalization Act 30 Years Later

Nicole Woitowich, Clinical Trials are Better at Including Women, But There's a Way to Go

The summer of 1993 was an eventful time: Prince changed his name to a symbol, “Jurassic Park” was released and Congress passed the National Institutes of Health Revitalization Act, requiring the inclusion of women in clinical research.

Most people aren’t aware of this law, which requires that women be included in research to develop drugs, therapies and treatments. For decades, women were underrepresented in or excluded from biomedical research studies because they could become pregnant or their hormones were deemed “too complicated.” This caused large gaps in our understanding of how sex and gender inform health and disease.

The Revitalization Act has just entered its fourth decade. As a biomedical scientist who studies the intersection of sex, gender and science, I know this for certain: We still have a long way to go.

For the first 20-plus years after the legislation was passed, the idea persisted that females were simply “too complicated” to study, leaving us with an often one-sided view of biology. In response, the NIH introduced a policy in 2016 requiring scientists to consider the sex of their subjects when designing experiments and reporting and analyzing their data.

Now scientists are more likely to include both sexes in their research studies, and women account for approximately 48% of NIH-supported clinical trial participants. That’s phenomenal progress, but there’s still one major problem: Scientists routinely fail to analyze their data by sex. When this happens, we have no way of knowing if males or females respond to treatments differently or if there are fundamental differences in the way they are affected by certain diseases.