Skip to main content

New research from Berkeley Public Health shows that the way race is classified in epidemiological studies can have a substantial impact on effect estimates. The study, published in the American Journal of Epidemiology in January, builds on a body of research that finds that multiracial people are frequently excluded or deliberately misclassified to fit into discrete racial categories, co-author Tracy Lam-Hine, a UC Berkeley School of Public Health doctoral candidate, said.

“We find that these classification schemes are not valid measures,” Lam-Hine said. “Choices of one classification scheme over another may really change the findings of the study, even if it is not a study focused on race or ethnicity as a major focus. Thus researchers need to carefully think about why they’re using their chosen scheme, otherwise study results may be biased.”

Lam-Hine and others were working on a separate study, looking at various behavioral or demographic factors associated with experiencing HIV or PrEP-related stigma among clients of the San Francisco AIDS Foundation. Initial results from that research surprised them—they found that people of color seemed less likely to experience stigma than white clients. The team decided to explore and document that issue as well.

Lam-Hine said he hopes that the findings “push health researchers to be more thoughtful about how they choose to classify multiracial people, and to incorporate theory into those choices.”

Research: Multiracial people often misclassified in epidemiological studies © 2022 by UC Berkeley School of Public Health is licensed under CC BY-NC-ND 4.0 Creative Commons Credit must be given to the creator Only noncommercial use is permitted No derivatives or adaptations are permitted
  • What is CC BY-NC-ND 4.0?

    CC BY-NC-ND 4.0

    Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

    You are free to:
    • Share — copy and redistribute the material in any medium or format
    • The licensor cannot revoke these freedoms as long as you follow the license terms.
    Under the following terms:
    • BY Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
    • NC NonCommercial — You may not use the material for commercial purposes.
    • ND NoDerivatives — If you remix, transform, or build upon the material, you may not distribute the modified material.
    • No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.
    Learn more: