Bridging the gap: Addressing diversity in clinical trials

Originally published on the Greenphire website prior to the merger with Suvoda in 2025.

Clinical research is essential for developing more effective ways to prevent, diagnose, and treat diseases. Every medication, vaccine, and procedure that shapes our healthcare today has undergone rigorous clinical trials. However, despite the critical importance of these trials, representation within them is far from where it needs to be.

Understanding the Barriers

Historically, racial minorities and other underserved communities have faced significant barriers to participating in clinical trials. Commonly cited reasons include mistrust of the medical system, cultural biases, and language barriers. While these factors are certainly significant, they only scratch the surface of a more complex issue.

A key, yet often overlooked, barrier is the role of those who design the studies and establish inclusion and exclusion criteria. These can include clinicians, physicians, nurse practitioners, and research staff who have the authority and access to recommend clinical trials to patients. Unfortunately, bias among these people can prevent eligible patients from participating in trials, further exacerbating the disparities.

Research conducted by the Tufts Center for the Study of Drug Development highlights this issue. It found that minority patients, including Black, Latino, and Asian American participants, were twice as likely to experience negative interactions, such as racial microaggressions, from clinical research staff. These negative experiences lead to decreased patient satisfaction, diminished trust in healthcare providers, and a lower likelihood of participating in future clinical trials.

The Role of Gatekeeper Bias

In our diversity webinar earlier this year, Jenny Kim, Research Assistant Professor at Tufts University, discussed the impact of ‘gatekeeper’ bias on clinical trial diversity. Gatekeeper bias manifests in the exclusion criteria used in clinical trials. For instance, in a study focused on lung cancer trials, researchers found that nearly 58% of exclusion criteria were influenced by subjective judgments rather than objective medical data. This means that decisions about who can participate in a trial are often based on a clinician’s opinion rather than on clear, measurable criteria. Such biases disproportionately affect racial minorities, further limiting their representation in clinical research.

Challenges for the LGBTQIA+ Community

The lack of diversity in clinical trials is not limited to racial and ethnic minorities. The LGBTQIA+ community also faces significant challenges. Current research efforts are only beginning to address the unique needs of this community. For example, sexual orientation is rarely tracked in clinical trials, with only about 30% of research sites in the U.S. collecting this data. This lack of data hampers our understanding of how treatments may impact LGBTQIA+ individuals differently, particularly when considering intersections with race.

Moving Toward Solutions

So, how do we address these disparities and improve diversity in clinical trials?

1. Community Engagement: One of the most effective strategies is to engage directly with underserved communities. Building trust through partnerships with community leaders can help spread awareness about clinical trials and encourage participation. Community leaders can also play a key part in following up with participants, ensuring they remain engaged throughout the trial process.
2. Reducing Gatekeeper Bias: It’s essential to address and reduce gatekeeper bias within the clinical trial design and execution. This can be achieved by revisiting and revising exclusion criteria to ensure they are based on objective medical data rather than subjective judgments. Additionally, training clinical research staff on cultural competence and the importance of diversity can help mitigate the effects of bias.
3. Improving UX for Diverse Populations: The user experience (UX) in clinical trials is another area that needs attention. Ensuring that trials are designed with diverse populations in mind, from language support to culturally sensitive communication, can make a significant difference in participant retention and satisfaction. Diverse UX teams are better equipped to design inclusive experiences that cater to the needs of all participants.
4. Tracking and Utilizing Data on Sexual Orientation and Gender Identity: For the LGBTQIA+ community, it’s crucial to start tracking data on sexual orientation and gender identity in clinical trials. This information will help researchers understand how treatments affect different populations and ensure that the needs of LGBTQIA+ participants are considered in trial designs.

Diversity in clinical trials is not just a matter of fairness; it’s a scientific necessity. Without diverse representation, the effectiveness of treatments for all populations remains uncertain. By addressing gatekeeper bias, engaging with communities, improving the user experience, and expanding our understanding of underrepresented groups, we can move closer to truly inclusive clinical research.

The journey toward diversity in clinical trials is challenging, but with continued effort and commitment, it’s a goal we can—and must—achieve.