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(p. 7) Ethical Challenges Related to Participation of Adolescents and Young Adults with Intellectual Disability in Research 

(p. 7) Ethical Challenges Related to Participation of Adolescents and Young Adults with Intellectual Disability in Research
(p. 7) Ethical Challenges Related to Participation of Adolescents and Young Adults with Intellectual Disability in Research

Pamela G. Nathanson

, Theodore E. Schall

, and Chris Feudtner

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date: 26 March 2019

Case Description

A research team was conducting a study of growth among children, adolescents, and young adults with Down syndrome. The study methods included measurements and Tanner staging. Participants were recruited from a summer camp serving this population. Some participants required parental consent in order to participate, either because of their age (under 18) or because their cognitive disability limited their capacity to understand the information provided in the consent process. Other adult participants were deemed to have capacity to consent on their own.

One adult participant, Stuart (names have been changed to protect privacy), provided his own informed consent to participate. He had told the staff that he had completed some college courses and had worked at a law firm. He also appeared to have sufficient capacity to understand the risks and benefits of the study. Stuart did not want his parents to be informed about his participation in the study and had provided an alternative mailing address for study materials. The study staff did not determine whether Stuart had the legal right to consent for himself, nor did they contact his parents, who were unaware of his participation.

(p. 8) During the course of a study visit at the camp, Stuart was unable to provide a self-assessment of his Tanner stage. When study staff tried to guide him with clarifying questions to help him provide this information, he became flustered and seemed upset that he could not answer the questions. The investigator was informed, and she spoke with Stuart, offering to take a “quick peek” in order to provide the correct Tanner stage, and Stuart agreed. He and the investigator entered a private room for a minute or two and then came back out. A camp counselor who observed this interaction lodged a concern with the camp supervisors, who then notified Stuart’s parents. The parents then lodged a complaint with the institutional review board (IRB).

The complaint to the IRB launched a broader discussion at our institution about the ethical challenges related to the participation of adolescents and young adults (AYAs) with intellectual disabilities (ID) in clinical research.

Ethical Analysis and Discussion

This case raises several ethical challenges related to balancing the rights of AYAs with ID to participate in research with the obligation to protect a potentially vulnerable population from research harms. These challenges exist at both the structural and individual levels. At a structural level, challenges include determining whether a particular research project that includes AYAs with ID is ethical and determining what additional training of frontline research personnel and IRB members will help AYAs with ID to participate fully and safely in important clinical research. At an individual participant level, challenges include assessing the capacity of AYAs with ID to consent to research and determining additional safeguards that need to be put in place in order to protect individual participants with ID from harm during the course of research.

Intellectual Disability and Balancing the Right to Participate with Protections from Harm

The American Association on Intellectual and Developmental Disabilities (AAIDD, n.d.) defines ID as “a disability characterized by significant limitations in both intellectual functioning and in adaptive behavior, which covers many everyday social and practical skills . . . [and] originates before the age of 18.” Intellectual functioning refers to an individual’s mental capacity and is generally assessed using an IQ test, while adaptive behavior is “the collection of conceptual, social, and practical skills that are learned and performed by people in their everyday lives” and can include interpersonal skills, problem-solving, (p. 9) activities of daily living, use of money, and so on. ID includes conditions like Down syndrome, Fragile X syndrome, Rett syndrome, inborn errors of metabolism, and autism spectrum disorder.

The AAIDD cautions that determining that an individual fits the definition of ID does not tell the whole story and that factors such as community and family environment, linguistic and cultural diversity, and the availability of additional supports can impact the assessment of ID and should help tailor support plans for each individual. Given this complexity, the fact that an individual has been identified as having ID does not mean that individual lacks the capacity to make a particular decision at a particular time, as his or her decision-making capacity will vary depending on the nature of the decision, the level of complexity, and the kinds of support available at the time.

Given the historical abuses of persons with disabilities detailed in the research ethics literature (Diekema, 2006; Krugman, 1986), some may question whether persons with ID should ever participate in research. Furthermore, given the disproportionately high rates of sexual violence experienced by people with ID (Davis, 2009), research involving “private” parts of the body poses more potential concerns. In recent decades, the widespread desire to protect individuals with ID from research exploitation has come into conflict with the growing recognition that persons with ID also have a right to participate in and benefit from research. The trend toward inclusion coincides with the emergence of the disability rights movement, which has encouraged individuals with a variety of disabilities to determine their own participation in various aspects of society (Chandler, 2016; Pfeiffer, 1993).

This conflict reflects a broader change in American society, as the scientific and medical worlds transitioned from a paradigm of protectionist paternalism to one of respect for individual autonomy. As with individuals with typical intellectual development, participation of subjects with ID may now be considered ethical when the individual has capacity to provide consent, when a surrogate determines by substituted judgment that the individual would want to participate if he or she was able to understand and express his or her wishes, or when a surrogate determines that participation in research is in the subject’s best interest.

Since participation in research can have both individual and community benefits, researchers should strive to find appropriate means of inclusion that respect the capacities and strengths of potential subjects with ID.

The Right to Participate in Research

Inclusion in research is crucial to developing generalizable knowledge about and improving care and services for AYAs with ID. It is ethically inappropriate (p. 10) to systematically exclude AYAs with ID from research studies and imperative that the ID community contribute to and benefit from research. Equality of opportunity to shape and participate in research is important for developing policy, improving care, and tracking how social and economic changes affect vulnerable communities.

Advocacy groups AAIDD and The Arc (2010) released a joint position statement on research that promotes additional research on ID that must be “adequately financed, well designed, focused on relevant topics, conducted with the highest ethical standards, presented in formats accessible to multiple audiences, and have a positive impact on people’s lives,” while also acknowledging the potential for exploitation of this vulnerable population. The position statement also encourages the inclusion of individuals with disabilities and their families into research design and the dissemination of results in formats that are easily accessible and understandable for people with ID and their family members.

Dignity and Autonomy

Respect for the dignity of AYAs with ID means respecting their privacy and confidentiality. In our case example, the researcher’s suggestion that she take “a peek” might have constituted a threat to Stuart’s dignity or created perceptions that he was not treated with dignity. To respect subject dignity, researchers ought to ensure that the environment and procedures of the study are comfortable, secure, private, and accommodating of subjects’ needs. The fact that the investigator assessed Stuart’s Tanner stage also raised concerns regarding sexual abuse, given the sensitive nature of the exam. In deference to concerns about sexual abuse of AYAs with ID, the investigator might, with Stuart’s agreement, have asked for a chaperone to accompany Stuart during the brief examination, thereby reinforcing the professional nature of the exam and also providing an additional witness in case of misunderstanding.

Respect for the personhood of potential subjects with ID requires giving them the opportunity to choose, to the extent that they are able, whether they want to participate in research. From the ethical principle of autonomy, we derive the need for voluntary, informed choice about research participation, despite the cognitive or other limitations with which AYAs with ID may present. Respect for the autonomy of AYAs with ID therefore usually will require that researchers accommodate their study design, methods, and consent processes to support the strengths of subjects with ID. We discuss some relevant techniques later.

(p. 11) Benefits of Participation

While bioethicists and researchers devote a significant amount of time to ensuring the protection of human subjects from research, a group’s access to research can also impact access to important social goods. The ethical principle of justice requires that the benefits of research be distributed fairly and not denied to communities or groups based on real or perceived differences of ability.

Participation in research can be beneficial for individuals or communities. Individual benefits may include early access to therapeutic agents not yet approved for medical use or personal feelings of meaningful contribution. Community benefits may include better understanding of relevant conditions, creation of generalizable knowledge that can improve medical or psychosocial care, or translation of findings into better policy or legislation. When research does not specifically target the community of AYAs with ID, inclusion in research ensures that “general populations” are truly representative and that any interventions that are developed can be used safely and appropriately by AYAs with ID or their families.

Scientific Reasons for Inclusion

There are sound scientific reasons for including individuals with ID in research. Since many of the conditions that cause ID (e.g., autism, Down syndrome, Fragile X syndrome, etc.) also cause additional medical and psychiatric comorbidities, clinical research on these conditions may particularly benefit individuals with ID, and excluding them from participation would be discriminatory. Furthermore, inclusion of individuals with ID whose physiology may be atypical in research on general populations may help researchers to better gauge the efficacy and safety of interventions in a diverse group of subjects. Such diversity is important for the development of treatments suitable for the true “general population” likely to need them.

Techniques to Enhance Participation of AYAs with ID in Research

Certain techniques may help AYAs with ID to more fully participate in clinical research, including the consent/assent process.

(p. 12) Well-Planned Procedures

Inclusion of community members and advocates in the planning phases of a research project can help keep the protocol, including consent procedures and documentation, within the range of acceptability both for participants and for the IRB. The typical expectations that IRBs have for the consent process (e.g., the provision of written explanations, the primacy of signatures) may be inappropriate for research involving AYAs with ID. Modified consent and assent procedures, such as exceptions or alternatives to the usual documentation requirements, may be more appropriate. Techniques such as collaboration and consultation with advocacy groups or holding focus groups of AYAs with ID or their families can help researchers plan a study design that supports subjects in their full and voluntary participation.


As with other subjects, spending more time at each study visit may help AYAs to better understand the study and build a relationship with the study team. Time can be especially important for developing relationships with AYAs with ID, as it takes time for a study team to learn nonverbal cues or other communication styles specific to subjects from this population. In addition, AYAs with ID may require a consent process that is staged over time, with initial information provided at one visit, and follow-up visits scheduled after the participant has had time to process the initial information, perhaps with the assistance of support persons. This staging can help reduce anxiety and support clearer decision-making.


When they can, researchers should consider and manage the amount of ambient noise and light, adequate space for support persons or adaptive devices, and other issues that can facilitate or hinder engagement between study team and subjects. Researchers should always consider the physical accessibility of the research location and whether it will allow for adequate privacy for sensitive conversations. Like other subject groups, AYAs with ID may benefit from a consent process and other study procedures that occur in familiar or comfortable spaces which allow for easier communication (Cambridge & Forrester-Jones, 2003). Asking for consent or assent in a familiar space may allow study subjects or researchers to more easily use the communication tools, such as graphic symbols, signs, or photographs, that the study subject uses on a regular basis.

Involving Support Network

Members of the AYA’s family or other support persons may be valuable in helping researchers understand the best ways to communicate with the subject. (p. 13) They may be able to help identify when additional information is needed, provide support to subjects in expressing their wishes, and assist researchers in looking out for signs of distress that they might not otherwise recognize. At the request of the AYA or the legal guardian, other members of the AYA’s support network, including physicians, social workers, case managers, clergy, or other providers, may be able to facilitate understanding and communication between the study team and the AYA.

Creative Communication Techniques

Communication strategies that are effective for individuals with ID have been developed, though they are not universal: communication methods must be individualized to maximize the strengths of each AYA with ID. Caregivers, family members, and potential subjects themselves can help researchers to understand the best way to individualize communication methods for a specific person.

Using both written and verbal communication may be helpful, as well as pictograms and other visual tools that simplify and clarify important concepts. It may be necessary for the researcher to learn and use basic sign language for work with specific populations or individuals (Cambridge & Forrester-Jones, 2003). AYAs with ID who rely on aided augmentative and alternative communication modes can benefit from individualized translation of relevant information into the formats best suited for their needs (Wilkinson & Hennig, 2007), including digital formats. Researchers should collaborate with local advocacy groups or experts in speech and language therapy when developing a plan for communicating with subjects with ID.

Balancing Simplicity with Completeness

Researchers developing consent and other study materials for AYAs with ID must be careful to balance their desire for simplicity with completeness of information. Researchers may be challenged to reduce the complexities of certain studies into content that can be understood by participants with ID, but just as with recruitment of potential subjects with language or cultural differences, consent discussions and other materials must be catered to the recipient of the information.

The Right to Be Protected from Harm

While research is key to improving health outcomes and improving policy, it also has the potential to harm individuals and communities.

The ethical principle of beneficence requires that health care providers and researchers protect patients and subjects from harm. This principle is also (p. 14) sometimes referred to as “non-maleficence.” Protection from harm can occur at a structural level, through regulations, IRB protections, and institutional level efforts, or at an individual level through the interactions between investigators and individuals with ID who are participating in research.

Group-level protection from harm evokes a larger question of justice, which requires that subjects be selected fairly. Research should not pose greater risks to subjects with ID than to those without ID. Furthermore, the choice to do research only on people with ID should be made on the basis of directly benefiting people with ID, and not on any other basis.

Individual-Level Protections

Important protections for AYAs with ID participating in research can be implemented at the individual participant level, including techniques to improve valid consent or assent and to ensure that ongoing participation is voluntary.

Consent and Capacity

Under ideal circumstances, all potential research subjects are assessed for their capacity to consent to the particular research protocol prior to being included in a study. Key elements of a full consent process include having participants explain their understanding of the study, the risks and benefits involved, their alternatives to participating, the potential consequences to themselves of participating or not, and their understanding of the voluntary nature of their participation and their ability to withdraw. For subjects who do not seem to understand the information or to be able to explain it to the recruiter, a formal capacity assessment should be obtained. There are tools designed for this purpose which can be found in the academic literature (Dunn et al., 2006).

The presence of an ID does not necessarily equate to an inability to provide consent for participation in research, and individuals with ID should be approached with the presumption of ability to consent unless a screening process indicates otherwise. One challenge when working with a population with known ID, for example a study that is recruiting patients with Down syndrome, is determining which individuals in the population may have capacity and which do not. For individuals with known ID, the first step prior to assessing capacity would be to determine whether a guardianship is in place. If the subject has a guardian, the guardian would provide consent and the subject would provide assent if capable, similar to a parent consenting for an adolescent child while the child provides assent. In our case example, the study team might have determined prior to the start of the study whether Stuart’s parents were his legal guardians. Answers to the questions that arose (p. 15) after the fact, about whether it was ethical to have respected Stuart’s desire to avoid contact between the study team and his parents, would have followed from the parents’ legal status: legal guardians should have been contacted for their consent, while parents without legal guardianship should not have been.

For individuals with a known ID but no guardian, a screening for indicators of capacity must be done for each individual and for each study. An individual with ID may be able to consent for some studies but not others, depending on the complexity of the study and the information necessary to understand the risks and benefits of participation. Historical or contextual information can be obtained from the potential subject’s support people or from prior medical records (if available) indicating whether the patient has or lacks capacity to consent to medical care. As Stuart was only able to present his own views of himself and his capacity to the study team, the team was not able to gain insight from Stuart’s support people.

Another challenge is recruiting from a population where some potential subjects have ID and others do not. In these cases, the difficulty is in knowing when to screen. Researchers must be careful not to stereotype potential participants as able or unable to provide consent based on the presence or absence of known ID. As in our case study, some individuals with ID may present with seeming capacity unless the recruiter knows to look closer. And others without known ID may not have the capacity to consent. Given this uncertainty, all participants in such studies should be screened for capacity.

Once an individual is determined to lack capacity for consent, the researchers must identify a legally authorized representative (LAR) to participate in the consent process. Some subjects may have the capacity to identify an authorized decision-maker even if they cannot consent themselves to participate in research. For those who do not have the capacity to name a surrogate, in many places, the LAR for research would be defined legally the same as an authorized decision maker for clinical care (Association for the Accreditation of Human Research Protection Programs, n.d.). In Stuart’s case, a determination that he lacked consent to participate during one phase of the study would mean he would need a LAR to continue to participate. Even though Stuart’s parents were not his legal guardians, he nonetheless could have selected them as legally authorized representatives once he had been found to lack capacity to consent.


Federal regulations define assent as “a child’s affirmative agreement to participate in research. Mere failure to object should not, absent affirmative agreement, be construed as assent” (Department of Health and Human Services, (p. 16) 2016). If an IRB determines that a research project requires assent for participation, the subject’s capacity to provide assent should be assessed. Capacity of minors and individuals with ID to provide assent is often overlooked, since the parent or LAR has already provided permission. But researchers should take care to ensure that the subject providing assent also has a basic understanding of the requirements of participation in the research and their ability to withdraw assent (or to dissent) at any time.

Assent can be a troublesome concept to translate into practice. If the process of obtaining assent does not provide a genuine choice about study participation that will be respected, then the process becomes ethically suspect. In circumstances where participation in a study provides access to an intervention with the potential for direct benefit to the participant, the IRB may determine that permission of parents or guardians may override an AYA’s refusal of assent, and, in such cases, the IRB and the study team should question whether an assessment of capacity should be sought, given that dissent would be overriden. Researchers should make the assent process, including any conditions or limitations that are being placed on assent, as clear as possible to avoid confusion about what is being asked or the degree to which the answer will be honored. As with consent, assent can also be challenging because obtaining informed assent requires researchers to communicate at a highly individualized, developmentally appropriate level with each subject. Researchers may struggle as capacity may not be tied to chronological age and flexible communication skills may be necessary to facilitate the conditions in which an AYA can give assent.

Continuous Consent

Continuous consent allows participants to reexamine their participation in the context of changing personal circumstances, supports participant autonomy, and reflects researchers’ respect. Continuous consent procedures vary across a spectrum, from less formal “reaffirmation” checks to a full re-consent procedure complete with IRB-approved paperwork (Wendler & Rackoff, 2002). Like other research participants, AYAs with ID stand to benefit from continuous consent, during which they should be regularly reminded about the study and its salient details, reoriented to the current study phase, and asked clearly whether they would like to continue.

Watching for Signs of Dissent

Researchers should monitor subjects for signs of dissent that arise at any point in the course of the study. Signs of dissent include pain, agitation, consistently turning away from the researcher, and other physical actions (pulling away, etc.). While pain is considered a universal indicator of withdrawal of consent (p. 17) (Thomsen 2012), nonverbal expressions may sometimes be inaccurately understood as indicating dissent (Wendler & Rackoff, 2002). This is a prime example of the challenges of balancing protection of subjects against their right to participate in research. Researchers should develop a clear process for managing the suspicion of participants’ dissent.

Researchers also need to monitor for unusual willingness to continue so as to avoid coercion or undue inducement and ensure voluntariness. Some individuals with ID may not understand their right to withdraw, may want to avoid embarrassment, or may fear being rejected by their medical team and will indicate their desire to remain in a study even when it is inconsistent with their goals or values. These situations require constant awareness and understanding of behaviors common to the population being studied or specific to the individual.

Structural Protections

In addition to individual-level protections, structural protections built into the design, approval, and implementation of a research project may help protect AYAs with ID from harm. These additional protections may include enhanced scrutiny or requirements of the IRB review process, or additional training for and oversight of study staff.

Enhanced IRB Scrutiny

IRBs reviewing study protocols that include AYAs with ID should include or bring in representation from relevant groups as necessary. Depending upon the study, the most appropriate choice of representatives may be AYAs with ID themselves; family members, advocacy groups, or professionals with experience working with ID populations; or members of more than one of these groups. As with most other kinds of review, the IRB should also include experts in capacity assessment and the ethics of research on vulnerable populations. When an IRB regularly reviews research protocols that include people with ID, the IRB should consider recruiting experienced community advocates to join its ranks.

Some IRBs may request documentation of consent or assent via audio or video taping, which adds another dimension to the ethical complexity of the research itself. IRBs should ensure that enhanced scrutiny does not undermine subject dignity.

Enhanced Participant Protections

IRBs may request that researchers confer with community and advocacy organizations prior to and during research to gain the input and approval of outside stakeholders and ensure the research is acceptable to a broader community. (p. 18) This kind of collaboration can help protect the public trust in research. Third-party organizations may be asked to participate in the ethical oversight of research recruitment and participation by providing observers to ensure the continuous assent/consent of participants. Such oversight can ensure that neither the sponsoring institution’s interests nor those of the principal investigator (PI) are prioritized over the best interests of study participants.

Subject Advocates and Chaperones

When subjects are likely to be particularly vulnerable or need ongoing decision support, or when other concerns exist about voluntariness of participation, subjects may be offered individual subject advocates to support them one on one through the research process. Subject advocates can assist in communication between researchers and subjects by clarifying questions and answers and promoting the safety and respect of subjects. They can also facilitate the consent or assent process by bearing witness to a subject’s agreement. Unlike research coordinators and other members of the study team, research advocates’ primary duties are to the research subjects, so they are better positioned to fulfill these duties. Importantly, subject advocates constitute a risk to subjects’ privacy, so they should be selected with care and only introduced to potential subjects with their agreement.

Subjects should also be asked for their agreement to the observation of chaperones, who may be involved in studies where neither parents nor subject advocates are present during physical contact between study staff and subjects. For studies that routinely involve examination of or contact with sensitive body parts, institutions should develop appropriate policies governing involvement of advocates and/or chaperones, regardless of the gender of the researcher and the subject.

Research Personnel Training

Structural protections may be implemented at the study staff level through enhanced training related to research with populations with ID, including topics such as enhanced communication techniques and recognition of potential signs of distress among study participants.

Consent/assent techniques: The skills necessary to appropriately obtain consent or assent from AYAs with ID are teachable and can be learned by study team members. Training on human research protection rules, with emphasis on vulnerable populations, should be made available by the host institution on an ongoing basis, but individual PIs still are ultimately responsible for ensuring that they and their teams are well versed in the relevant ethical concepts and behaviors. Working with AYAs with ID creates a further obligation to ensure that study team members can communicate effectively and respectfully with the population.

(p. 19) Beyond basic competence in communicating with the group being studied, research personnel should be trained to take the time to gain insight into the communication behaviors of specific study participants. Study team members should be supported in learning any new skills necessary for translating information into the best medium or format for the subject. Researchers should also learn to think critically about the behaviors they encounter to assess whether those behaviors are consistent with capacity determinations and continuous consent/assent.

Identifying red flags: Study team members should be trained to spot red flags in the consent/assent process, during which they should be alert for behaviors that might indicate that informed consent or assent has been compromised. Subjects who quickly agree to participate without hearing all relevant information may not understand all the elements of research participation or may not be engaged fully in communicating with the study team. Subjects who insist upon enrollment may be laboring under the therapeutic misconception and believe that the research is likely to accrue benefits to them personally. Subjects who change their minds frequently or inconsistently engage in the consent process may be expressing an underlying unwillingness through their ambivalence. Furthermore, if subjects become flustered, reluctant, or resistant as they are participating in study procedures (as in Stuart’s case), these attitudes or behaviors may well signal that the subject may no longer wish to participate and that the subject’s continued consent should be reassessed. Study team members should be trained to respond to these red flags by thinking critically and either stopping the consent process or study procedures and elevating their concerns to other team members, the PI, the IRB, or another body as appropriate.

Case Outcome

After questioning all people involved, the IRB’s investigation reassured all parties, including the parents, that no form of abuse had occurred and that Stuart had not experienced any adverse events other than his sense of frustration when he was unable to answer the questions regarding Tanner stage.


In our case example, the investigator did not critically reevaluate whether Stuart’s behavior cast doubt on his capacity to consent to treatment or his (p. 20) willingness to continue participating. His behavior (confusion, agitation, a lack of understanding of what the study entailed) suggested, however, that his consent to participate might have been compromised. Instead of offering to help Stuart answer a question he did not understand, the investigator might have instead stopped the research activities to make a new determination of capacity and conferred with her peers about whether Stuart’s continued participation was appropriate. More broadly, not planning for this chain of events, whereby a subject starts to express confusion or misgivings about participating, either verbally or behaviorally, puts not only participants but also investigators and research staff at risk. While some have wisely argued that in times of doubt the best default is to assume that a participant ought to be removed from a study unless there is a compelling reason to believe that they want to continue to participate (Wendler & Rackoff, 2002), it is far better to anticipate these times of doubt than to be caught unprepared, to take steps to prevent such circumstances from arising, and to respond to questionable or concerning situations with well-formulated plans.

Discussion Questions

  1. 1. How does the history of abuse of individuals with ID through research impact current research efforts with this population?

  2. 2. What are the ethical and scientific justifications for including populations with ID in clinical research?

  3. 3. Why is it important to assess capacity to consent to research for individuals with ID? Is this more or less important than assessing capacity to consent for any other potential research subject?

  4. 4. How can researchers modify the consent process to accommodate the needs of individuals with ID? How might these modifications help other potential research participants?

  5. 5. What are some structural protections that can help to balance the rights of individuals with ID to participate in research with their right to be protected from harm? How do these differ from current structural protections?

  6. 6. What are some individual-level protections that can help to balance the rights of individuals with ID to participate in research with their right to be protected from harm? How do these differ from current individual-level protections?


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