A new study from Massachusetts General Hospital published in JAMA Surgery highlights the pitfalls of basing clinical recommendations on data that is too heavily skewed towards one race or ethnic group.
The current guidelines for breast cancer screening issued by the US Preventative Services Task Force recommend beginning mammograms at age 50 for women at average risk. David Chang, PhD, MBA, MPH, of the Mass General Department of Surgery, wondered if, given that these guidelines were developed based on data from primarily white women, they were not inclusive enough to address racial differences and thus putting other populations at risk.
To investigate, Chang and his team analyzed data from the Surveillance, Epidemiology, and End Results database of the National Cancer Institute covering women ages 40 to 75 who were diagnosed with breast cancer during the years 1973 to 2010.
They found that nonwhite women – specifically Hispanic, Asian and African-American women – tended to get breast cancer in their 40s – a full two decades earlier than whites, and too soon to benefit from mammograms begun at age 50.
These results support the development of guidelines calling for earlier initial screening of some nonwhite women, but also highlight a larger issue, according to Chang.
“The situation with breast cancer is one of the best examples of how science done without regard to racial differences can produce guidelines that would be ultimately harmful to minority patients,” said Chang in a press release. “Flawed science can harm more people than flawed clinical care, which is why it is so important to detect and eventually eliminate these sorts of hidden biases in the scientific literature.”
The JAMA Surgery paper also notes that, while some may be concerned that lowering the screening age for certain patients could lead to overdiagnosis and overtreatment, current improvement in screening technologies and clinical practice could reduce those risks. The fact that earlier screening would apply only to nonwhite women and the cost savings that may result from improved outcomes in minority patients whose cancer is detected earlier may mitigate the costs of additional screenings.
Chang and his team will soon be starting a new course at Harvard Medical School, titled, “Culturally Sensitive Science: Preventing Medicine’s Contribution to Social Bias and Disparity,” to teach future physicians and physician scientists on ways to detect hidden biases in current scientific literature.