"We have yet to achieve bias-free health care. This has serious public health implications as we know that higher levels of screening lead to lower levels of mortality. Clinicians need to be aware that they may be sending signals, even unintentionally, that lead minorities to believe they are being discriminated against," said Dr. LaVera M. Crawley, an assistant professor at the Stanford University Center for Biomedical Ethics.
The researcher further says that exactly what those signals are will need to be determined in future studies, but the relationship between perceived discrimination and failing to get regular screenings is strong.
For their study, Crawley and colleagues analyzed data from the California Health Interview Survey, which examined cancer screening trends among African-American, American-Indian/Alaskan-Native, Asian and Latino adults.
The study published in Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research, was based on information gathered from about 11,245 respondents.
"Respondents answered yes or no to 'was there ever a time that you would have gotten better medical care if you had belonged to a different ethnic group?' However, we were not able to ask why they felt discriminated against," Crawley said.
The researchers found that minority women who perceived racial discrimination were 34 percent less likely to be screened for colorectal cancer, and 48 percent less likely to be screened for breast cancer, compared with women of any racial group who did not perceive discrimination, researchers found.
The results were slightly different among minority men, as men who perceived racial discrimination were no less likely to be screened for colorectal cancer than those who did not perceive discrimination.
However, if they had a regular source of health care, they were 70 percent less likely to receive colorectal screening if they perceived racial discrimination.
"This contradicts the general assumption in public health that having a usual source of care is a cure all. If men felt discriminated against by their regular health care provider, they did not receive screening. So there is something else factoring in," Crawley said.
The researchers say that the specific factor would need to be explored in further research, but it may be that there are specific racial stereotypes that apply to men that would not apply to women.
"For example, African American men may be stereotyped as being more violent, which would affect how doctors respond to them and thus create a potential for discrimination," said Crawley.
According to Crawley, the consequences for delayed screening are dramatic.
If detected early, five-year survival rates for colorectal and breast cancer are approximately 90 percent.
However, if caught in later stages, the survival rate for colorectal cancer is 10 percent and 23 percent for breast cancer.
"The longer someone delays screening the worse the outcome. Perception of discrimination may be driving the differences we see in outcomes among minorities," said Crawley.