Bias in cancer trials

For many years I served on NHS research ethics committees.  One aspect of clinical trials that always concerned us was how representative any trial was of the population.  This matters a great deal, as biased samples may give erroneous results or miss results that are of crucial importance  

Now, new research has revealed bias and stereotyping among clinical and research professionals who recruit patients to enrol in cancer clinical trials. The findings are published online in CANCER, a peer-reviewed journal of the American Cancer Society (ACS).

It is important to include diverse patients in clinical trials to ensure that the results will apply to patients in the general population.

One form of bias is in the selection of those on the trail.  The proportion of racial and ethnic minorities participating in cancer clinical trials is persistently lower than the proportion of minorities in the U.S. population at large.  This has the potential for giving a false perspective.

So, does bias by healthcare and research professionals help explain why racial and ethnic minorities are not adequately represented in clinical trials? 

A team led by Dr Raegan W. Durant, of the University of Alabama at Birmingham, conducted interviews of cancer centre leaders, principal investigators of clinical trials, referring clinicians, and research staff at five U.S. cancer centres. A total of 91 individuals were interviewed.

Five prominent themes emerged from the interviews:

1. Respondents noted language barriers and other factors that made communication with potential minority clinical trial participants difficult.
2. Several respondents stated that they did not perceive potential minority patients to be ideal study candidates after they were screened for cancer clinical trials.
3. Some respondents described clinicians’ time constraints and negative perceptions of minority study participants as challenges.
4. When respondents discussed clinical trials with minority patients, they often addressed misconceptions to build trust.
5. For some respondents, race was perceived as irrelevant when screening and recruiting potential minority participants for clinical trials.

Dr Soumya Niranjan, the first author of the report states that,

“Examples of the stereotypes we observed included perceptions that African Americans were less knowledgeable about cancer research studies, less likely to participate due to altruism, or simply less likely to complete all facets of the research study,”  

These and other examples of bias based on stereotypes of potential minority participants raise concerns that non-whites may be offered fewer opportunities to participate in cancer research studies.

Dr Niranjan also noted that even when research and healthcare professionals use race-neutral stances during clinical trial recruitment, this approach may overlook some of the well-established methods of engaging and recruiting potential minority participants in a culturally tailored manner. 

The authors make clear that not all healthcare professionals and research is biased. Still, the findings do indicate that more care needs to be taken in ensuring clinical trials are sufficiently representative of the population, or whether a particular section of the community needs to be targeted. 

Only by acknowledging the bias can it bet better identified in trials.