Barriers and Facilitators to Recruiting Study Participants in Host Genomic Studies

September 1, 2020 by Madison Dixon, MPH Student, Emory University School of Medicine, and Ridgely Fisk Green, Office of Genomics and Precision Public Health, Centers for Disease Control and Prevention, Atlanta, Georgia

a Manhattan plot wiht COVID-19 virus

Host genomic studies play an important part in understanding disease susceptibility, severity, and outcomes. These studies require a minimum number of participants to ensure statistical power. Participation barriers and facilitators must be considered in order to effectively recruit a suitable number and diversity of eligible participants.

The COVID-19 host genetics initiative aims to explain the role of host factors in the current pandemic. Studies might need to include populations that are at increased risk for severe illness, such as those with pre-existing medical conditions including obesity, type 2 diabetes, and serious heart disease. In addition, studies on disease incidence and severity in the United States would need to include populations experiencing higher rates of severe illness, such as Black, Hispanic, and Native American people. While the differences in incidence and severity in these groups is not thought to be due to genetics, any genetic studies done should strive to be representative of the larger population. Research studies often provide the most benefit to the populations that are studied, and some of these populations, such as Blacks, Hispanics, and Native Americans, have been historically underrepresented in medical research.

Available information on trends in participation rates point to an overall decline in participation in epidemiologic studies in general. Several reasons cited by studies include

Increases in the number of research studies mean that some potential participants receive multiple requests, which not only results in participants perceiving their participation as not important but also as an intrusion into their personal lives.
Research suggests that participation in community activities, organizations, and volunteering events has decreased across the United States and Western countries, which can translate into lack of participation in research.
Evidence suggests that people are less likely to participate in a study if the research aim has no personal salience or relationship to them.

Some findings are particularly relevant to groups experiencing more severe illness from COVID-19. These include

Participation rates for those older than 65 have decreased significantly in the recent years.
Studies exploring underrepresentation of racial/ethnic groups, including Black, Hispanic, and Native American people, in epidemiologic studies have found that barriers to participation include concerns about being experimented on and mistrust of medical professionals.

In addition to those for epidemiologic studies, DNA studies have their own considerations. They require participants to submit some form of genetic material, such as saliva or blood, which may raise the participant’s perception of risk. Some additional barriers to DNA study participation include:

Concerns about data privacy, as genetic data are viewed as uniquely identifiable
Lack of interest and no perceived benefit to the participant

Past injustices, such as the Tuskegee Study, are at the root of mistrust among Black, Native American, and other populations that have been historically underrepresented in research. Potential discrimination and fear of being experimented on are valid concerns that contribute to the lack of trust in the scientific community. In order to effectively recruit diverse populations for genetic research, the barriers specific to these populations must first be addressed.

Higher risk populations are underrepresented in research in general, but especially in genomic research. Findings about challenges to DNA study participation that are specific to higher risk populations include

The majority of those diagnosed with a chronic disease self-reported having limited knowledge about genetics in one study, especially among older participants.
The general population has limited knowledge of the medical applications of genetic testing. This is especially true in communities that lack access to culturally appropriate information on genetics.
Lack of understanding regarding biospecimens and how they are used for research led to decreased willingness to participate among Black and Hispanic participants.
Black participants reported that genomic studies presented issues of personal identification and potential discrimination due to genomic-based policies.
Many eligible participants from Black, Hispanic, and Native American populations are not aware of opportunities to participate in genetic studies.

Approaches that address barriers to DNA study participation include:

Providing participants with their individual results at the end of the study
Providing compensation for participation
Engaging with the community
Having diversity among research team members
Striving for transparent communication between the research team and participants

As an example, The Precision Medicine Initiative’s All of Us Research Program has had some success in recruiting a diverse range of participants by establishing public trust and redefining the patient-researcher relationship through addressing some of the ethical, legal, and social issues that are associated with the research initiative. These efforts have included

Engaging with community-based groups to help researchers develop valuable community relationships, effectively recruit diverse populations, and make participants aware of other genetic studies and resources
Ensuring that informed consent language is appropriate and includes details the purpose of the study and efforts to maintain participant privacy
Providing opportunities, such as educational sessions, to learn more about genetic knowledge as well as how genetic studies can benefit future generations

Failure to include and purposefully recruit higher risk and traditionally underrepresented populations can lead to an increase in health disparities and disproportionate health burden. More research into the facilitators and barriers for populations who are typically more at risk for disease in the United States are needed to increase participation from these underrepresented populations.

Some action items to make studies more inclusive in the future include:

Thoughtful and deliberate engagement with the community throughout the entirety of the study.
Identification of potential facilitators and barriers specific to the population of interest.
Tailoring recruitment strategies to the population.

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