This chapter provides ethical guidance unique to individuals in a vulnerable situation. ‘Vulnerability’ in this context refers to a substantial incapacity to protect one’s own interests owing to impediments such as lack of capability to give informed consent, lack of alternative means of obtaining medical care or other expensive necessities, or being a junior or subordinate member of a hierarchical group (CIOMS and WHO 2016).

Vulnerability may vary over time; people may be considered vulnerable at some stages in their lives but not in others. Vulnerability is both universal and specific. Researchers need to take into account what people are vulnerable to, and whether and how research might create, exacerbate or otherwise interact with participants’ existing vulnerabilities (Lange et al 2013; Rogers and Lange 2013).

Research with vulnerable individuals is necessary, to answer questions that are important to people with similar characteristics. Such research is often crucial in reducing the health inequities experienced by these groups. For this research to meet the ethical principles of justice and mana, researchers should ensure that vulnerable individuals or groups are not a convenience sample; the group must stand to benefit from the knowledge, practices or interventions that result from the research. Research should be conducted in partnership.

The ethical principles of respect for people and whakapapa require researchers to pay attention to the rights of all participants, taking particular account of potentially vulnerable people whose individual characteristics and circumstances, in the context of the study, place them at increased risk of harm.

Researchers must avoid excluding groups of people based on stereotypes. A person’s individual vulnerability depends on context as well as group characteristics, and can vary according to circumstances. Researchers should not think solely in terms of entire groups being vulnerable. Instead, they should look for the specific characteristics and contexts that may create vulnerability – particularly where multiple risk factors co-exist – and address them appropriately.

Balancing access to research with avoiding exploitation

6.1 Researchers should not exclude participants from research simply because they may be vulnerable.

6.2 Researchers should include the least vulnerable participants where it is consistent with their study aims.

6.2.a Researchers must balance inclusion of vulnerable participants in research with the reduction of unnecessary risk and exploitation.

6.3 Researchers should provide all potentially vulnerable participants with appropriate support to help them make informed decisions about participating in a study.

6.4 Researchers must balance the rights of vulnerable individuals and groups and any potential benefits of their participation in research against any increased risk of harm.

6.5 Researchers must consider pursuing special protection of vulnerable participants’ rights and welfare, while balancing this with respecting the autonomy of those individuals.

Diminished capacity to consent

For the purposes of these guidelines, there are three groups of people to consider when seeking informed consent:

  • those who can give informed consent
  • those who require assistance to give informed consent, and
  • those who cannot give informed consent.

An unconscious person with no ability to communicate is an example of someone who cannot give informed consent, and marks the limit of the supported decision-making model.

6.6 It should be noted that almost any person, with the right support, is capable of providing informed consent. A person-centred, supported decision-making model should involve:

  • providing information to each potential participant on an individual, face-to-face basis
  • allowing adequate time for the process of obtaining informed consent
  • delivering information in a form appropriate to the individual being consented, such as with tailored patient information sheets and consent forms which have been trialled with a group of people who are similar to potential study participants
  • if the individual is unable to read or write, using verbal or other alternative methods of communication to convey information and record informed consent
  • taking into account factors such as level of understanding, reading ability, and knowledge about research and research requirements
  • involving members of the person’s support network, while ensuring that potential participants experience no coercion in making their decision whether or not to take part in the research
  • in the case of children with disabilities, providing assistance aligned to their identification as both a child and a disabled person
  • if necessary, hiring a qualified person to conduct the supported decision-making process
  • keeping a permanent record of the process, as evidence that information was provided in an appropriate manner and informed consent was obtained free from coercion.

The term ‘capacity’ refers to individuals’ everyday ability to make decisions or to take actions about matters that affect them. Capacity may depend on the particular context as well as the nature and complexity of the decision involved. Capacity and competency are usually used interchangeably. Capacity refers to the ability to make decisions. Competence on the other hand refers to the ability to perform actions needed to put decisions into effect.

To have capacity/competence, participants must be able to understand the information relevant to their decision to participate in research, assess it, retain it, make a decision and communicate that decision.

The Code of Health and Disability Consumer Rights 1996 (the Code) identifies that every consumer of health and disability services must be presumed competent unless there are reasonable grounds for believing that they are not competent.[1]

Where researchers have reasonable grounds for believing that participants do not have the capacity to consent to research, the research protocol must include a method for determining a person’s capacity to consent. There is no all-purpose test for what will be considered reasonable and the researcher will need to decide based on the particular facts.[2]

Diminished capacity may be due to a number of factors; for example, early dementia or other brain disease, brain trauma, drug intoxication, pain, distress, mental illness, disability, or reduced intellectual capacity. Research with participants who have diminished capacity is important, to address the health and disability needs of these groups.

6.7 Researchers should assume that every individual has the capacity to make an informed choice and give informed consent unless they have reasonable grounds for believing that this is not so.

6.8 People who have diminished capacity to make decisions about their participation in a study are entitled to make informed decisions to the extent that their level of capacity allows (Code of Health and Disability Services Consumers’ Rights 1996(external link)).

6.8.a In considering individuals’ capacity to consent, researchers need to take into account the level of complexity of the study. They must provide information in an appropriate format (e.g. they should consider abbreviating or simplifying it, if necessary).

6.9 Capacity to provide informed consent can change over time, so researchers must consider the need to reassess a participant’s capacity over the course of the study, and take into account any changes in capacity with regards to ongoing participation in the research.

6.10 Where an individual has diminished capacity, that individual still has the right to make informed choices and give informed consent, to the extent appropriate to their level of capacity.

Supported decision-making

A supported decision-making regime comprises various support options that give primacy to people’s will and preferences and respect human rights. It should provide protection for all rights, including those related to autonomy (the right to legal capacity, the right to equal recognition before the law, the right to choose where to live, etc) and rights related to freedom from abuse and ill-treatment (the right to life, the right to physical integrity, etc).

A supported decision-making regime should not overregulate the lives of persons with disabilities in a way that impacts their capacity (United Nations Convention on the Rights of Persons with Disabilities 2006(external link)).[3]

All people risk being subject to ‘undue influence’; however, this risk may be exacerbated for those who rely on the support of others to make decisions. Safeguards for the exercise of people’s legal capacity must include protection against undue influence; however, such safeguards must respect people’s rights, will and preferences, including the right to take risks and to make mistakes.

6.11 Such a person may be able to exercise their right to consent to participate in research through supported decision-making.

6.11.a Supported decision-making differs from substituted decision-making (consenting on behalf of another person) in that the latter approach does not involve the participant in the decision-making process. See section on substituted decision-making.

6.11.b In the context of supported decision making, the role of supporters (e.g. friends, family, whānau) is to facilitate an individual’s decision-making process. The potential participant should choose these supporters, and there should be no conflict of interest involved in the arrangement.

6.11.c The term ‘support’ includes non-conventional methods of communication.

6.11.d The level of support provided should reflect the level of complexity in a particular study and be sufficient to enable an individual to make a decision about whether to participate.

6.11.e Supported decision-making results in an individual making their own informed choice.

6.12 For guidance on research involving an individual who has inadequate capacity to provide informed consent, even with appropriate support, see Research with Adults who Cannot Provide Informed Consent

Participants in a situation of power imbalance

Power imbalances do not inherently represent an ethical issue; indeed, all relationships are unequal in some way. Rather than focusing on inequalities themselves, researchers should focus on whether the inequalities are creating problems.

Unequal power relationships may pose a risk in a study, depending on who is conducting the research and in what context. Such relationships include those between patients and doctors; people in residential care or supported accommodation and their caregivers; students and teachers; children or prisoners and custodians; refugees and government employees; members of the military and their superiors; committed mental health patients and health professionals; employees and employers; and in some cases Māori, Pacific Peoples, women, LGBTQI people, disabled people and people who are low-income and service providers within those communities who are receiving a service.

The power imbalance involved in these relationships may limit the extent to which consent to participate in research is truly voluntary; for example, potential participants may expect that they will get preferential treatment if they agree to participate, or may fear that they will be disadvantaged if they refuse.

6.13 Researchers must identify and take steps to minimise the risks of any unequal relationship that might restrict a person’s freedom to choose to participate in research.

6.13.a Researchers should be aware that, in the context of research, it is often the case that researchers, rather than participants, hold the position of power.

6.14 When an individual declines to participate in or decides to withdraw early from research, the decision should not result in any negative consequences, such as unfair discrimination, a lower level of care or dismissal from employment.

6.15 Researchers must consider the potential for a power imbalance to influence their study results.

6.15.a For example, individuals in an unequal power relationship may be unwilling to answer sensitive study questions (such as questions about sexual or illegal activity) honestly.

6.15.b Similarly, they may over-report benefits because they want to please the researcher by providing the answers they believe the researcher wants to hear.

6.16 Researchers should consider whether hierarchical relationships may compromise a participant’s privacy outside the study, and mitigate this risk.

6.16.a For example, research in a workplace may reveal the personal medical information of an employee participant to an employer researcher.

6.16.b Researchers should be aware of the extreme difficulty of protecting participant confidentiality when undertaking research in environments that intrinsically lack privacy, such as prisons, rest homes, hospitals and workplaces.

Managing unequal power relationships

Participants in imbalanced power relationships may be vulnerable to being ‘over-researched’ (that is, participating in research to an extent that becomes fatiguing or unethical) where researchers have relatively easy access to them as research populations. People in this position should not bear an unfair share of the burden of participating in research; nor should they be excluded from its benefits.

6.17 Researchers should take account of vulnerabilities arising from unequal power relationships in deciding whether to seek out members of certain populations as research participants.

6.18 Researchers must identify and take steps to minimise the risks of any unequal relationships.

6.18.a Suitable steps may include informing participants of their freedom to withdraw or decline to participate without adverse consequences, using an independent person to undertake the consent process and providing an independent advocate to participants to support their decision-making.

Research with children and young people

Children have equality of value and dignity with all other human beings. Research involving children and young people is important, to understand their unique physiologies and health and disability needs. However, researchers working in this area should acknowledge that additional protections are necessary for the safety and emotional and psychological security of participants.[4]

Research involving children and young people raises particular ethical concerns, including:

  • children and young people’s capacity to understand what the research involves
  • in the case of adolescents, whether their consent alone is sufficient for them to participate
  • the potential for undue influence from parents, peers, researchers or others
  • the potential conflicting values and interests of parents and children (NHMRC 2018).

6.19 Researchers should only conduct research with children if comparable research with adults could not adequately/appropriately answer the research question and the purpose of the research is to gain knowledge relevant to the health needs of children.

6.19.a Researchers must balance the benefits of inclusion of children and young people in health and disability research with the need to protect them against unnecessary harms.

6.20 Before undertaking research with children or young people, researchers must ensure that:

  • if children from a range of age groups can answer the study question, the study involves older children in preference to younger ones
  • people experienced in working with children are involved in the design, supervise and conduct the research
  • if a child participant is under 16 years old and lacks the necessary capacity to give legally effective consent, the researcher gets consent for the child to participate from their parent or legal guardian (Care of Children Act 2004)
  • they are aware of cultural considerations such as differing compositions of families and/or guardianship rights having been appointed to wider family members
  • if consent is provided by a parent or guardian, the researcher still gets the child’s assent (agreement) to participate whenever possible, and respects a child’s refusal to participate in research unless:
    • the purpose of the research procedures or interventions is to provide potential therapeutic benefit to the child participant, and
    • through the research the child would receive therapy via the research for a condition for which there is no medically acceptable alternative.
  • if a child turns 16 during the course of a study, and if they have sufficient capacity the researcher seeks their consent to continue participation.

6.21 Only one parent or legal guardian is required to give consent on the child’s behalf.[5]

6.21.a However, if the research includes treatment which significantly differs from routine care[6], the researcher should consider the views of the other parent or other legal guardians.

6.21.b Guardians in exercising these responsibilities in relation to a child must act jointly (in particular by consulting wherever practicable with the aim of securing agreement) with any other guardians of the child. I.e. the consent of all guardians is not always required, even when the treatment is other than routine[7].

6.21.b.a However even with non-routine procedures, a practitioner should usually be able to rely on a guardian’s assurance that any or all other guardians are in agreement. A researcher cannot be expected to always know how many guardians a child has or whether it would be practicable to consult with all of them in the circumstances.

6.21.c If the researcher becomes aware that the person who gave consent on the child’s behalf has lost their authority to give such consent, they should seek consent from the child’s new legal guardian as soon as practicable.

Consent and assent with children and young people

6.22 Researchers must respect the developing capacity of children and young people to be involved in decisions about participating in research. This is supported by the United Nations Convention on the Rights of the Child (UNCRC) which obliges health professionals to ensure children’s voices are heard and given due weight in accordance with their level of maturity.

6.22.a The capacity of each individual child or young person affects whether their consent or assent is necessary and/or sufficient to authorise participation. It is not possible to attach fixed ages to each level of capacity, as levels vary from child to child.

6.22.b A child or young person may be at different levels of capacity for different studies, depending on the type of research and its complexity.

6.22.c Age alone has been shown to be an inaccurate marker of the level of children’s competence.[8] Other internal factors which will impact on the ability of a child to consent are prior experience of illness, level of independence, ethnicity, culture, and temperament.

6.22.d It is the responsibility of health professionals to impart information in a way age appropriate to the child. The time that a child has to digest and understand the information is another relevant factor (and may be a barrier to obtaining meaningful consent in an acute setting).

6.23 All competent children/young people must provide their own informed consent.

6.24 Participants aged 16 years or older who are competent should provide their own informed consent to participate in any medical research without health professionals needing to make further inquiries as to capacity.

6.24.a There may be circumstances where a 16 or 17-year-old is incapable of giving consent, whether because of disability, unconsciousness or other reason. In such a situation a guardian may be able to give a legally effective consent or if there is no guardian present in New Zealand, or a guardian cannot be found with reasonable diligence, consent may be given by a District Court judge or by the chief executive of the Ministry of Social Development, or services may be provided through right 7(4) of the Code of Rights.

6.25 Different categories of maturity, and corresponding levels of competence may include:

  • infants and very young children, who are unable to take part in discussion about research and its effects
  • young people, who are able to understand some relevant information and take part in limited discussion about the research, but are not competent to consent, although researchers should ask for their assent and respect their dissent
  • young people who are mature enough to understand and consent, and are not vulnerable through immaturity in ways that warrant the need for additional consent from a parent or guardian.

6.26 Research protocols (or institutional/departmental policies) must include a method for establishing the degree to which child participants are able to provide informed consent. To have adequate competence for this, the child must have sufficient understanding and maturity to adequately comprehend the proposed treatment or research participation and its potential consequences.

6.26.a Consent and assent are dynamic, continuous processes; researchers should check throughout the study to ensure they are maintained. If during a study a child participant develops the capacity to give consent, the researcher must obtain their consent, which will replace their parents’ consent on their behalf.

6.27 Researchers must provide a range of suitable information sheets, consent forms and assent forms to a level appropriate to the literacy levels of all participants. Information sheets for children should be child-friendly, and provide a suitable level of information, appropriate to the study’s level of risk and the nature of the children’s involvement. Illustrations may be helpful.

6.27.a Researchers should engage young children with limited cognitive capacity, discussing the research and its likely outcomes at their level.

6.28 Researchers should keep research data on child participants for at least 10 years after the child has reached the age of 16 years.

6.28.a Children should be offered the choice to withdraw consent to the continued use or retention of personally identifiable health research data (and tissue) once they reach the age of 16 years.

6.29 Researchers need to undertake good ethical practice and pay particular attention to ethical issues concerning children or young people if study participation involves the disclosure of sensitive information, such as sexual activity, drug use or abuse.

6.30 Researchers should consider making special provisions for protecting children’s privacy, to ensure children provide accurate information, so they do not feel a need to lie to please their parents.

Researcher vulnerability

Researchers can also experience vulnerability. The process of collecting data or undertaking field work can be a stressful exercise for a researcher, particularly if the research involves illness or trauma. Researchers may bear witness to participants’ experiences involving intense suffering, trauma, loss or other experiences that may cause an affective response in the researcher. Along with emotional risks, there can be physical risks to researchers: for example, threats or abuse.

Challenges cited by researchers conducting qualitative research include issues relating to use of researcher self-disclosure, feelings of guilt and vulnerability, the difficulty of listening to untold stories and exhaustion (Dickson-Swift et al. 2007).

6.31 Researchers should ensure they have adequate support to counteract the effects of vulnerability they may experience when conducting research.

[1] Right 7(2) of the Code of Health and Disability Services Consumers’ Rights 1996.

[2] Skegg P and Paterson R Health Law in New Zealand p216

[3] For guidance on determining capacity see Gilbert et al 2017.

[4] For more guidance see the Ethical Research Involving Children website(external link) and Ministry of Health 1998.

[5] Section 36(3)(a) Care of Children Act.

[6] Medical treatment for a child that is not routine in nature is considered for the purposes of the Care of Children Act to be “an important matter affecting the child. The Act considers that it is the responsibility of all guardians of a child to determine for or with the child decisions about important matters affecting the child.

[7] The general provisions of section 16 of the Act should not be read in a way which frustrates the effect of section 36 which indicates that legally effective consent may be given “by a guardian of the child.”

[8] The Code of Rights does not specify any age for consent and makes a presumption that every consumer of health services is competent to make an informed choice and give informed consent, unless there are reasonable grounds for believing that the consumer is not competent.

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