Racial and Ethnic Disparities in Research Studies: The Challenge of Creating More Diverse Cohorts

Lindsey Konkel


Environ Health Perspect. 2015;123(12):A297-302. 

In This Article


The shafts of midmorning sun that spill into San Francisco's Visitacion Valley belie the dank gloom inside Crystal Paniagua's home. The 27-year-old shows a community health worker where cockroaches have been coming in through light fixtures and electrical outlets in the dilapidated two-bedroom apartment she occupies with her mother and four kids in the Sunnydale–Velasco Projects—one of the poorest, most crime-ridden neighborhoods in San Francisco.

Paniagua's son Darian, a shy seven-year-old with asthma and roach allergies, hangs back as she opens the black box where she keeps his medications—allergy pills, nasal decongestants, eczema cream, and an albuterol inhaler and spacer. "He's been telling me for a few days that his nose is hurting," says Paniagua. She explains to the community health worker that his cough gets worse at night. The medications do little to help ease his breathing, which sounds like whistling.

Minority kids like Darian—his mother says he has Mexican, Puerto Rican, Dominican, and Samoan ancestry—are more likely to deal with pollution, poor housing, and asthma than their white counterparts.[1] Yet people of color are less likely to be included in biomedical research studies to address asthma and other environmentally related diseases, such as cancer and diabetes, that disproportionately affect minority communities.[2,3]

The U.S. Census Bureau predicts that within 30 years the nonwhite proportion of the American population will shift to more than 50%.[4] A failure to create more racially diverse research cohorts, some experts say, could exacerbate existing health disparities if those most affected by disease continue to be excluded. Others call it a missed scientific opportunity to fully understand the factors that lead to poor health and disease. Still others point to the high cost of racial and ethnic health disparities. By one estimate, reducing racial and ethnic health disparities would have saved the United States over $1.2 trillion in direct and indirect medical costs between 2003 and 2006 alone.[5] New multidisciplinary studies examining the complex associations between genes, socioeconomics, and environmental exposures only underscore the need to include more minority participants in biomedical research.