Contact

Duke Health News

919-660-1306

Durham, N.C. -- Duke University Medical Center researchers say clinical trials that promote behavior modification to prevent cardiovascular disease may challenge African Americans' ethnic identity, making the trials less effective in this group than in non-African American groups.

In a paper featured in the April 28, 2003, issue of Ethnicity and Disease, the researchers say that a greater understanding of cultural appropriateness and biases could increase the recruitment and retention of African Americans in behavior modification trials and improve the outcomes for African American participants in those trials.

"Cultural differences and connections to cultural identity are important to understand when asking African Americans to change their behaviors; in some cases it's like asking them to change who they are and how they view themselves," said Jamy Ard, M.D., fellow in general medicine at Duke University Medical Center and lead author of the paper.

In this model, Ard said bias is defined as a set of beliefs and preconceived ideas that are formed based on perceived differences between cultures or an ethnocentric point-of-view. Bias is referred to as an inherent property of the differences between cultures and not a premeditated act of racism.

"When an investigator constructs a behavior modification clinical trial, most likely there will be cultural biases in the design and data collection that are not overtly obvious," said Ard. "By understanding these biases, we can create a culturally sensitive model that will benefit both researchers and African American participants."

Behavior modification trials, particularly ones that focus on preventing cardiovascular disease, often ask participants to lower their fat intake, increase exercise and lose weight. Ard said that the design of many of these trials ensures that African Americans will not be as successful as they could be.

"What makes someone African American?" he asked. "Culturally this is a complicated question, but, for example, food is definitely a part of that equation. If I ask an African American in a clinical trial to stop eating foods that she associates with her culture, she is going to be much more resistant to that change than if I suggest foods that are already part of her lifestyle, but are much healthier for her," said Ard. "Behavior changes will only be adopted when they do not cause any sustained cultural discomfort."

Socioeconomic status can also a major barrier for some African Americans in clinical trials. "If we are talking about people who are trying to make ends meet economically, we need to think about how that impacts their abilities to make substantial lifestyle changes," Ard said. "If a person works two jobs, when do they have time to exercise or come to nutrition classes? What if they can't afford to join a gym? We have to consider the potential implications on everyday life when designing clinical trials. Our interventions have to work in the real world with a diverse group of people."

The Duke team suggests that researchers consider their own cultural biases as they design clinical trials. They also recommend the use of focus groups to help guide appropriate interventions. But even in the focus groups, Ard said there is a danger of oversimplifying suggestions.

"Even within the African American community, there are many levels of what we call 'acculturation.' The more a person is immersed into mainstream culture and less into African American culture, the less bias that person will have regarding behavior modification that uses a mainstream cultural approach," he said. "It's important when talking to African Americans that researchers understand the concept of African American acculturation and put that into proper perspective."

Ard said distrust of the medical and research community is another important factor to understand when attempting to recruit African Americans into clinical trials. This distrust, said Ard, is rooted in long standing negative experiences with clinical trials, most notably the Tuskegee Syphilis Experiments.

Between 1932 and 1972, the U.S. Public Health Service (PHS) conducted an experiment on 399 black men in the late stages of syphilis. The men, who were mostly poor sharecroppers from Alabama, were not told they had syphilis. The doctors did not treat the men so they could observe the destructive final stages of the disease, which can include tumors, heart disease, paralysis, blindness, insanity and death.

In addition to educating researchers about these events, Ard suggests that more African American researchers are needed to help overcome this lack of trust.

"I'm not saying that non-African American researchers can't be culturally sensitive to African Americans in their studies. But when the researcher is African American, and the trial is designed from that cultural perspective, it goes a long way toward eliminating biases and building trust within the community."

Ard said the next steps in validating this model include conducting more extensive focus groups and compiling a set of cultural variables that researchers should consider when designing culturally appropriate clinical trials that include African Americans. Subsequent focus groups will include African American participants from various demographic groups and other regions of the country. Ultimately, clinical trials comparing standard and culturally appropriate lifestyle clinical trial methodologies will be required to understand the true impact on outcomes for African Americans, Ard said.