How to do Inclusive Research When ‘Legal Capacity’ for Informed Consent is Questioned

Researchers describe a CRPD-compliant participatory research project with people with neurodegenerative disorders where the ‘legal capacity’ to give informed consent was questioned.


The human rights model of disability, as articulated by the United Nations (UN) convention on the Rights of Persons with Disabilities (CRPD), calls for inclusive, participatory research and underscores the right to free and informed consent, even in cases of diminished decision-making capacity.

A new article published this month in Disabilities documents the process of conducting participatory research with disabled participants with neurodegenerative diseases (e.g., Alzheimer’s disease, dementia) who do not meet standard criteria for ‘mental capacity.’ With reference to their “Smart and Health Ageing through People Engaging in Supportive Systems (SHAPES) Project,” the researchers describe their efforts to implement the CRPD’s human rights framework for informed consent in situations where mental capacity is in question.

The authors, Richard Lombard-Vance, Evelyn Soye, Delia Ferri, Emaa McEvoy, Malcom Maclachlan, and Sari Sarlio-Siintola, explain:

“The participation and meaningful contribution of SHAPES Platform users is essential to the SHAPES ethos of inclusivity. In ensuring a person-centered approach throughout, it is vital that the voices of older persons are heard in the research, development, and piloting of the SHAPES Innovations and Platform. Moreover, we recognize the importance of the contribution of the diversity of SHAPES Platform users, including vulnerable adults who are often excluded from research due to their presumed inability to give informed consent. Exclusion would limit the findings of the research and further marginalize those who could conceivably derive considerable benefit from it. In line with the provisions of Article 12 and Article 25 CRPD, SHAPES respects the inherent legal capacity of all persons to give their free consent to participation.”

The authors begin their article by discussing the CRPD as revolutionary framework that is foundational to their research with ‘vulnerable adults.’ Making certain that their work does not perpetuate harm, neither in practice nor in language, they note that ‘vulnerability’ is an “open textured and ambiguous, elusive notion which is used in many different disciplines” and clarify that although “SHAPES uses the term’ individuals experiencing vulnerability,’ to link the idea of vulnerability to the inherent vulnerabilities of human being as well as structural inequalities and barriers faced by specific cohorts.

The authors conducted a systemic review of vulnerable adults in participatory research projects. Participatory research, with its origins in the disability rights movements of the 1970s, can take many forms. It is, however, fundamental that participatory research is done with the community being studied.

“Involvement is research done with or by patients and the public, not to, about or for them,” they write.

The authors argue that participatory research is more ethical and also benefits both the participants and the academic researchers.

“Psychosocial benefits reported for co-researcher older adults included the following: increased self-confidence; personal growth; intellectual stimulation; knowledge and skill acquisition; enjoyment; feelings of achievement or satisfaction; being valued; feeling useful; being able to “give something back”; challenging pre-existing assumptions and prejudices; the development of relationships with other co-researchers, academics, and the wider community; and opportunities for activism or career progression.”

However, questions remained about how to implement participatory principles with vulnerable populations who may not be able to consent to participate fully. Current standard practice is that it is best to leave these vulnerable adults out of research because they are considered not to have the capacity to consent. However, on the other hand, this lack of inclusion of vulnerable adults in research has resulted in the neglect of this population.

The capacity to consent is quite tricky to discern, especially when researchers frequently prioritize mental capacity over legal capacity. This is because mental capacity can fluctuate over the course of your life, depending on whether or not your cognitive function is medically impaired or diminished due to a disease like Alzheimer’s or dementia. Whereas legal capacity is inalienable and must be afforded to everyone regardless of diminished mental capacity. Unfortunately, this means that the national laws frequently prioritize mental capacity over the CRPD’s definition of legal capacity and systemically leave out the perspectives of psychosocially disabled people.

Article 12 of the CRPD notes:

“Persons with disabilities enjoy legal capacity on an equal basis with others in all aspects of life.”

According to the authors, this is an example where the CRPD is helpful in shifting standard practices. The authors use the findings of their SHAPES project to highlight how the CRPD provides a pathway for achieving informed consent from all participants through supported decision-making practices. Supported and shared decision-making practices are frequently considered to be best practice in healthcare and research, creating a space of equal dignity for researcher/practitioner to come together and plan courses of treatment, or in this case, discern, together, what the participant/patient is able to do and not do.

The SHAPES Project took place across ten EU member states and is built on the principles of respecting human dignity and the intrinsic values of all persons. The researchers consider two things when working to retrieve consent from vulnerable adults.

  1. Whether the person needs support in order to make a decision related to the project activities.
  2. If their decision is legally valid under national law, what would be required under national law to facilitate decision-making or consent?
“Shaping the environment around the person may enable functioning and is consistent with the social model of disability… it should be assumed that all participants have the potential to make decisions; however, tools should be available to assist in the exercise of decision-making skills and methods,” the researchers explain.
“If needed and requested by the person, the researcher may involve a support person in important appointments to make notes and to assist the person to understand or remember choices. Such persons may include caregivers, trustees, advocates, communications assistants, interpreters, or guides. Support persons have a role in providing relevant information about a potential or actual participant’s will and preferences at various stages of research participation, from pre-participation to initiation, to ongoing participation or withdrawal. Supporters have a role in supporting persons not only to understand and make decisions, but to remember their choices, to express and give voice to their opinions and decisions, and to action or implement their decisions.”

To secure full inclusion and to guarantee high ethical standards, the researchers outlined the following guidelines for an appropriate consenting process.

  1. Rights-based approach – all researchers share the belief that each participant has the inalienable legal capacity to provide meaningful consent. Each participant must also be made aware that there are accessibility measures and decision-making supports available to them.
  2. Accessibility measures – if the participant would be able to consent to accessibility measures such as plain language materials, information in visual form, or more time to discuss choices, the participant must be given these options.
  3. Allow for decision-making supports – “individuals should be afforded the opportunity to have another person explain the information provided by the project and to communicate the SHAPES is built on the principles of respecting human dignity and the intrinsic person’s preference in relation to the decision…To this end, SHAPES assumes that all persons have the potential to choose one or more trusted support persons to assist them in exercising their legal capacity.”
  4. Decision-making as a cyclical process and (re)evaluation – The authors describe informed consent as a cyclical and ongoing process. Indeed, participants can, of course, withdraw their consent at any given moment of the research.

This article offers a useful frame of reference for bringing the principles of the CRPD to participatory research in vulnerable populations while respecting the right to informed consent. In recent years, service-user and survivor researchers in the mental health fields have called attention to the need for inclusive, participatory research methods, more robust informed consent practices, and supported-decision making interventions to avoid coercive treatments.



Lombard-Vance, R., Soye, E., Ferri, D., McEvoy, E., MacLachlan, M., & Sarlio-Siintola, S. (2023). Applying the ‘Human Rights Model of Disability to Informed Consent: Experiences and Reflections from the SHAPES Project. Disabilities, 3(1), 28-47. (Link)


  1. One thing that has always puzzled me is the readiness of mental health providers to determine that a person is not legally competent to make a medical decision, such as the decision to refuse a medical treatment, yet they frequently declare that the same individual is competent to make other decisions.

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