Clinical Researcher—October 2026 (Volume 40, Issue 5)
SPECIAL FEATURE
Muhammad Waseem, MBBS, MS, FAAP, FACEP, FAHA, FSSH, CPI, FACRP
Engaging vulnerable populations in research during periods of crisis, uncertainty, or social disruption is both essential and challenging. Vulnerable populations, including children, older adults, individuals with disabilities, racial and ethnic minorities, immigrants, refugees, people experiencing homelessness, low-income communities, and those with limited health literacy, are often disproportionately affected by public health emergencies, natural disasters, economic instability, and social unrest. Yet these groups are frequently underrepresented in research, limiting the applicability and equity of scientific findings. Even under normal circumstances, they often face structural barriers to healthcare and research participation.
During crises, these barriers often intensify. Additional barriers, such as fear, mistrust of institutions, transportation challenges, competing life priorities, limited access to technology, language differences, and privacy concerns, can further reduce participation. For example, during the COVID-19 pandemic, many immigrant families were reluctant to participate in studies due to concerns about immigration status. At the same time, low-income households often lacked reliable internet access for virtual research activities.
However, including vulnerable populations in research is essential to advancing health equity, improving clinical outcomes, and ensuring that scientific discoveries apply to the communities most affected by disease and health disparities. Yet engaging in these populations becomes increasingly challenging during periods of societal disruption. Public health emergencies, economic instability, natural disasters, political polarization, social unrest, and widespread misinformation can significantly hinder researchers’ ability to recruit, enroll, and retain participants from vulnerable groups. For experienced researchers, successfully engaging vulnerable populations requires moving beyond traditional recruitment methods and adopting strategies grounded in trust, flexibility, community partnership, and cultural humility.
Understanding Vulnerability in Context
Vulnerability is not solely an individual characteristic but often reflects social, economic, political, and environmental conditions. A participant may become more vulnerable during periods of instability because of job loss, housing insecurity, reduced access to healthcare, or increased caregiving responsibilities.
Researchers must recognize that crises can create new vulnerabilities while exacerbating existing disparities. For example, during the COVID-19 pandemic, many underserved communities faced higher infection rates, greater economic hardship, and reduced access to healthcare. At the same time, these communities were often disproportionately represented among essential workers and those at greatest risk of adverse outcomes. A contextual understanding of vulnerability helps investigators to anticipate barriers and develop research approaches that respond to participants’ evolving circumstances.
Building and Maintaining Trust
Trust remains the cornerstone of successful engagement with vulnerable populations. Historical abuses in research, experiences of discrimination, privacy concerns, and perceived power imbalances between researchers and communities can fuel skepticism about participating in research. Researchers must invest time in building authentic relationships with communities before recruitment begins.
Periods of social uncertainty often heighten mistrust. Communities may question researchers’ motives, worry about how their information will be used, or fear that participation could adversely affect immigration status, employment, healthcare access, or public benefits.
Trust cannot be established through recruitment materials alone. It must be cultivated through long-term relationships and meaningful engagement. Researchers should invest in partnerships with community-based organizations, faith leaders, schools, advocacy groups, and local healthcare providers that already have established credibility within the community.
Community advisory boards can play a particularly valuable role by guiding study design, recruitment strategies, consent processes, compensation plans, and the dissemination of findings. These partnerships help ensure that research priorities align with community needs rather than with an investigator’s interests alone. For example, researchers conducting studies in immigrant communities may collaborate with trusted community organizations to address confidentiality concerns and reassure participants that research data will not be shared with immigration authorities.
In addition, it may be reassuring to explain that agreeing to participate will often result in being assigned an identification number, removing personal information from the research records. Transparent communication about study goals, risks, benefits, confidentiality protections, and data use is particularly important during times of uncertainty, when misinformation may be widespread.
Addressing Social and Economic Barriers
Many vulnerable populations face competing social and economic priorities that can limit their ability to participate in research. During times of crisis or uncertainty, concerns about food insecurity, housing instability, employment, transportation, childcare, and access to healthcare often take precedence over research participation.
Researchers may underestimate the burden of study participation on individuals and families already under significant stress. Lengthy study visits, complex protocols, multiple follow-up appointments, and extensive paperwork can discourage enrollment and contribute to participant attrition. Minimizing participant burden should be a fundamental consideration in study design, not an afterthought.
Strategies to enhance participation include offering flexible scheduling, such as evening and weekend appointments; using virtual or hybrid study visits; conducting home-based data collection when feasible; providing transportation vouchers or parking reimbursement; offering childcare support; simplifying study procedures; and ensuring fair and appropriate compensation for participants’ time and effort. These approaches can improve recruitment, retention, and equity in research participation among vulnerable populations.
Investigators should also consider partnering with social service organizations and community health programs. While research should not replace social support, connecting participants with available resources demonstrates respect for their needs and may improve engagement.
Depending on the nature of the research, participation may include free physical exams, medical follow-up, and therapeutic interventions, such as medications. This could be a game-changer for future participants with limited or no health insurance. For example, a pediatric asthma study in an underserved urban community may integrate referrals to housing assistance, environmental remediation programs, or insurance navigation services as appropriate.
Enhancing Communication and Health Literacy
Effective communication is essential for engaging vulnerable populations in research, especially during periods of crisis, uncertainty, or rapidly evolving information. Many individuals face barriers that can hinder their understanding of research, including limited health literacy, language differences, cultural variations in communication styles, and exposure to misinformation from social media, community networks, or other sources. These challenges may shape how potential participants perceive research risks and benefits, affect their willingness to participate, and undermine trust in the research process. During public health emergencies or other periods of social disruption, the rapid spread of conflicting information can further complicate participants’ ability to make informed decisions about research participation.
Traditional informed consent documents often pose an additional obstacle. Many consent forms are written at reading levels above those of the general population and include complex regulatory language, medical terminology, and legal jargon that can be difficult to understand.
Even individuals with advanced education may struggle to fully understand lengthy consent documents, especially when they are experiencing stress, illness, financial hardship, or competing personal responsibilities. As a result, obtaining a signed consent form does not necessarily ensure meaningful understanding. Researchers should therefore view informed consent as an ongoing communication process rather than a one-time administrative requirement.
To promote truly informed decision-making, researchers should prioritize communication strategies that emphasize comprehension, transparency, and participant engagement. Plain-language consent materials at an accessible reading level can improve understanding and reduce confusion.
For participants with limited English proficiency, provide professionally translated documents and bilingual and bicultural research staff who can help bridge linguistic and cultural gaps, fostering trust and facilitating meaningful dialogue. Visual aids, infographics, and short educational videos can simplify complex concepts and make research procedures more accessible for individuals with varying literacy levels. Teach-back techniques, in which participants explain study information in their own words, can help researchers assess comprehension and address misunderstandings before enrollment.
These approaches not only strengthen the ethical foundation of informed consent but also enhance participant confidence, improve recruitment and retention, and promote more equitable inclusion of diverse and underserved populations in research. For example, a study involving immigrant families may achieve greater engagement by providing consent materials in multiple languages, using culturally relevant examples, and employing bilingual community health workers to explain study procedures. Similarly, researchers conducting studies in low-literacy communities may use visual storytelling, diagrams, or brief videos to explain research goals and participant expectations.
By tailoring communication strategies to the needs and preferences of the population under study, researchers can foster trust, enhance understanding, and empower vulnerable populations to make informed decisions about participating in research.
Transparency is equally important. Participants should clearly understand the study’s goals, risks, benefits, confidentiality protections, and data-sharing practices. Honest communication about uncertainty can strengthen credibility and trust. For example, in vaccine-related research, investigators may encounter participants influenced by misinformation on social media. Addressing concerns respectfully and providing evidence-based information can be more effective than dismissing fears outright.
Overcoming the Digital Divide
The rapid expansion of telehealth and remote research methods has transformed how researchers engage participants, particularly during public health emergencies, natural disasters, and other periods of social disruption. Virtual recruitment, electronic informed consent, online surveys, mobile health apps, wearable technologies, and remote monitoring systems can increase convenience, reduce travel burdens, and facilitate support for participation for individuals who might otherwise struggle to attend in-person study visits.
These approaches can be especially valuable for participants living in geographically isolated areas, those with mobility limitations, individuals with demanding work schedules, and families with significant caregiving responsibilities. By reducing logistical barriers, technology-enabled research can broaden participation and improve access to research opportunities.
Despite these advantages, reliance on digital technologies can inadvertently create new barriers and exacerbate existing inequities. Access to reliable internet, smartphones, computers, and digital literacy varies widely across socioeconomic, geographic, and demographic groups. Older adults, low-income households, rural communities, individuals with limited English proficiency, people experiencing homelessness, and some racial and ethnic minority populations may have limited access to the technology needed to participate in remote research.
Even when devices are available, participants may lack the technical skills or confidence to navigate electronic consent platforms, complete online surveys, or operate wearable devices. Consequently, relying exclusively on digital research methods may unintentionally exclude individuals already underrepresented in research, introducing selection bias and limiting the generalizability of study findings.
Researchers should carefully evaluate whether technology-based approaches could create disparities in recruitment, enrollment, retention, or data collection. Rather than assuming that digital solutions improve accessibility for all participants, investigators should assess the specific needs and capabilities of the populations they aim to engage.
Hybrid participation models that combine virtual and in-person options often provide the greatest flexibility and inclusivity, allowing participants to choose the method that best fits their circumstances and preferences. These approaches can help ensure that technological innovation enhances, rather than restricts, equitable participation.
Several strategies can help bridge the digital divide and promote more inclusive research participation. These include providing tablets, smartphones, or other devices to participants without access to technology; offering financial support for internet connectivity or mobile data plans; maintaining telephone-based alternatives for recruitment, consent, and follow-up; and providing technical assistance through dedicated support staff to help participants navigate digital platforms.
Researchers should also preserve opportunities for face-to-face interactions when appropriate, especially for participants who prefer personal communication or need additional support. For example, a community-based study of older adults may combine virtual follow-up visits with optional in-person appointments and telephone check-ins, ensuring participants remain engaged regardless of their technological capabilities.
Ultimately, technology should be viewed as a tool to enhance access and participation rather than a substitute for participant-centered engagement. By proactively addressing digital inequities and offering flexible participation options, researchers can reduce barriers, minimize selection bias, and ensure that advances in digital research methods promote greater inclusion, diversity, and equity in research participation.
Retention During Times of Instability
Retaining participants throughout a research study is often more challenging than initial recruitment, especially during periods of prolonged social, economic, or public health instability. Vulnerable populations may face circumstances that disrupt research engagement, including housing instability, relocation, changes in employment, loss of internet or telephone access, financial hardship, illness, caregiving responsibilities, and other competing life demands. These challenges can increase the risk of participant attrition and loss to follow-up, disproportionately affecting underrepresented populations.
High attrition rates can threaten study validity by reducing statistical power, introducing bias, and limiting the generalizability of findings, especially when those who withdraw differ systematically from those who remain enrolled. Effective retention requires a proactive, participant-centered approach that prioritizes relationship-building throughout the study lifecycle. Participants are more likely to remain engaged when they feel respected, supported, and valued by the research team.
Regular, respectful communication helps maintain connections and reinforces participants’ importance to the study. Researchers should use multiple contact methods, including telephone calls, text messages, e-mails, mailings, and communication through trusted community partners, to accommodate participants’ preferences and minimize disruptions from changes in contact information. Reminder systems for study visits, surveys, or follow-up assessments can further improve retention. At the same time, flexible scheduling and alternative data-collection methods can reduce participant burden and accommodate changing life circumstances.
Transparency and ongoing engagement are also critical to successful retention efforts. Participant newsletters, study updates, and periodic progress reports can sustain interest and foster a sense of partnership. Recognizing participants’ contributions with thank-you messages, certificates of appreciation, or appropriate compensation can further strengthen commitment to the study.
Importantly, researchers should share study findings with participants whenever possible, showing how their involvement advanced knowledge and improved health outcomes. For example, a longitudinal study of underserved families may maintain high retention by providing regular updates, offering virtual and in-person follow-up options, and maintaining consistent communication across multiple channels.
Ultimately, participants are more likely to stay engaged when they feel that researchers genuinely value their time, experiences, and contributions. By prioritizing flexibility, communication, transparency, and participant-centered engagement, researchers can improve retention, reduce loss to follow-up, and enhance the scientific validity and equity of their research.
Ethical Considerations During Crises
Conducting research with vulnerable populations during periods of crisis, instability, or social disruption poses unique ethical challenges that require careful planning and oversight. While research during these times can generate critical knowledge to improve health outcomes, inform policy, and address emerging needs, investigators must balance scientific advancement with their fundamental obligation to protect participants from harm, exploitation, and coercion. Participants may face heightened social, economic, and health risks during crises, making ethical safeguards even more important.
One significant concern is the potential for undue influence. During periods of economic hardship, financial compensation for research participation may carry more weight than intended, potentially influencing individuals to participate despite reservations about the study. Although appropriate compensation helps reduce participation burdens and recognize participants’ time and effort, investigators must ensure payments are reasonable and do not compromise voluntary decision-making.
Similarly, individuals with limited access to healthcare, social services, housing assistance, or other essential resources may view participation in research as necessary to obtain benefits or maintain relationships with healthcare providers. This concern is especially relevant when research activities are closely integrated with clinical care settings. Researchers must clearly communicate that participation is voluntary, that declining to participate will not affect access to medical care or other services, and that participants may withdraw from the study at any time without penalty.
Privacy and confidentiality are equally critical, especially when conducting research with stigmatized or marginalized populations. Participants may have legitimate concerns about how their personal information will be collected, stored, shared, and protected. These concerns may be heightened among immigrant communities, individuals with sensitive health conditions, survivors of violence, people involved in the justice system, and populations that have experienced discrimination, surveillance, or historical mistreatment.
Researchers should implement robust data security measures, limit access to identifiable information, use secure electronic platforms, and clearly explain confidentiality protections and their limitations. Transparency regarding data use and sharing can help build trust and ease concerns that participation could lead to social, legal, or economic consequences.
Institutional review boards (IRBs) play a critical role in ensuring that research involving vulnerable populations during crises remains ethically sound. IRBs should carefully evaluate study design, recruitment methods, compensation plans, risk-benefit assessments, and consent procedures to keep participant welfare the top priority. Community engagement and consultation can further strengthen ethical oversight by incorporating the perspectives and concerns of those most affected by the research.
Ultimately, ethical research in challenging times requires vigilance, transparency, respect for participant autonomy, and a commitment to justice. By upholding rigorous ethical standards and prioritizing participant protection, researchers can advance important scientific knowledge while preserving public trust and safeguarding the rights and well-being of vulnerable populations.
Conclusion
Engaging vulnerable populations in research during times of uncertainty requires more than traditional recruitment methods. It demands commitment to trust-building, community partnerships, cultural humility, flexibility, and participant-centered design. Researchers who recognize and address structural barriers are more likely to achieve meaningful inclusion, improve retention, and produce findings that are both scientifically rigorous and socially relevant.
By centering the experiences and needs of vulnerable populations, investigators can strengthen public trust in research and ensure that those most affected by health disparities remain represented in the evidence base that informs healthcare practice, policy, and future scientific discovery.
Muhammad Waseem, MBBS, MS, FAAP, FACEP, FAHA, FSSH, CPI, FACRP, is a Professor at Weill Cornell Medicine and an Attending Physician and Research Director for Emergency Medicine at Lincoln Medical & Mental Health Center, where he is also Vice Chair of the Institutional Review Board. He is also active with the Society for Simulation in Healthcare, Public Responsibility in Medicine and Research, the American College of Emergency Physicians, the American Academy of Pediatrics, and the American Heart Association.
