Topic: Consent to Participate in Research

What is ethical consent in research? 

When a research participant agrees to take part in research, they give their consent. This is referred to as ethical consent. Obtaining consent is a fundamental requirement of research ethics across all academic disciplines. To be valid and ethically acceptable, consent must be freely given and informed. 

Ethical consent is based on respect for human dignity and is grounded in principles from The Belmont Report:  

• Respect for equality, freedom, and self-determination 
• Protection against the risk of harm and unreasonable burden 
• Justice in procedures and in the distribution of benefits and burdens 

Free and informed consent is essential for safeguarding research participants and maintaining trust in research. Responsibility for ensuring ethical consent from participants rests with the researcher. In medical and health research, the norm of consent is codified in the Health Research Act (Unofficial English translation by UiO). In other disciplines, consent is a key principle in the national research ethics guidelines. 

Guidelines and guidance material 

Ethical Guidelines for Sami Health Research (Norwegian only) 

Read more about research ethics norms and guidelines here: 
Introduction to research ethics

Informed

Consent is only valid if it is informed, as described in the Health Research Act, the Guidelines for Research Ethics in the Social Sciences and the Humanities, and the Guidelines for research ethics in science and technology. This means that prospective research participants must receive sufficient and comprehensible information to enable them to make a genuine and independent decision about participation.

Researchers must ensure that research is conducted responsibly and that research participants are not exposed to unnecessary risk, harm, or disadvantage. This includes providing participants with sufficient information to assess the balance between risks and benefits associated with participation. It also means that researchers themselves must continuously assess whether it is ethically justifiable to continue the research. 

The information should normally include the purpose of the research, the methods and approach, what information will be collected, how it will be processed, stored, used, and potentially reused, as well as who will have access to the data. Participants should also be informed about any potential benefits that may result from the research, likely consequences, and risks of harm or disadvantage. In addition, they should be informed about relevant interests related to the organization and funding of the research. 

It is useful to think of consent as a process rather than a one-time event. Consent is obtained at the outset of a project, but researchers must ensure that the consent remains valid throughout the duration of the project and any subsequent use of the data or material. Participants should be able to ask questions and receive updated information at any time. 

For consent to be genuinely informed, researchers must also ensure that participants understand what the consent entails. Information must therefore be communicated in a language and at a level of precision appropriate to the target group. This is particularly important in research involving children, persons with cognitive impairments, or persons who do not speak the researcher’s language. This is related to the assessment of capacity to consent. See the section «Capacity to Consent» for more information. 

The researcher’s duty to provide information is an independent ethical responsibility and also applies in situations where consent to participate or consent to the processing of personal data is not obtained. This means that even in cases where research does not require consent, it may still be necessary to provide information to individuals affected by the research. One example is registry-based research, where data have already been submitted and anonymized, but where those who have contributed data to the registry should be informed about new research projects.

Providing Information About Risk 

Information about potential risks associated with participation in research is a key component of obtaining informed consent. The information must describe the types of harm, disadvantages, or burdens that may arise, how serious and likely they are, and what measures have been implemented to reduce risk. Harm, disadvantages, and burdens may be psychological as well as physical.

In order to provide adequate information about risk, researchers must assess both the severity and the likelihood of potential risks. Burdens that do not exceed what may normally be expected in everyday life or during routine examinations are generally considered to involve minimal risk. Participation that entails a genuine possibility of physical, psychological, social, or legal harm, such as research requiring medical interventions or involving vulnerable groups, is considered to involve high risk. In medical and health research, the interests of the participants must take precedence over the interests of research. In other fields of research, there are exceptions to this principle.

Voluntary

Consent must be voluntary and freely given, as described in the Health Research Act, the Guidelines for Research Ethics in the Social Sciences and the Humanities, and the Guidelines for Research Ethics in Science and Technology. This means that individuals must decide for themselves whether they wish to participate in research. Researchers must avoid all forms of undue influence, pressure, or manipulation. 

It is important to consider how the risk of perceived pressure can be minimized when obtaining consent, including who obtains the consent, how it is obtained, and when it is obtained. In practice, there may be several factors that make it challenging to ensure that consent is truly voluntary. Examples include situations where there is an asymmetrical power relationship between the researcher, or others responsible for recruitment, and the research participant, such as between a patient and healthcare personnel or between a pupil and a teacher. Another example is that pupils may feel pressured not to stand out if consent is obtained openly in a classroom setting. 

Another important aspect of voluntary consent is the right to withdraw, as described in the Health Research Act, the Guidelines for Research Ethics in the Social Sciences and the Humanities, and the Guidelines for Research Ethics in Science and Technology. Research participants must be able to withdraw from the research without having to provide a reason. Researchers should ensure that participants receive clear information about how this can be done. 

Explicit 

Consent must be documented. This means that researchers must be able to demonstrate what information participants have received and how consent was provided. As a general rule, consent should be given in writing, both to document the participants’ wishes and to ensure traceability and quality in the research process. 

In some cases, written consent may compromise participants’ sense of security or their anonymity. In such situations, oral consent may be a better alternative. For advice and guidance on how consent may be obtained in such cases, see Medical and Health Research in Low- and Middle-Income Countries. 

Exceptions

There are several exceptions to the general rule of obtaining consent. In some cases, research may be very difficult or impossible to carry out if the requirement for consent must be fulfilled. Nevertheless, it may still be ethically justifiable, and even highly important, to conduct the project. Where research is to be conducted without consent, a balancing of interests must be undertaken, taking into account, among other factors, societal benefit, potential disadvantages, and respect for the participants’ integrity and dignity.

Research Without Consent

The Guidelines for Research Ethics in the Social Sciences point out that there are exceptions to the requirement to provide information. This also means that consent is not obtained. Examples include research conducted in public spaces, research on public statements or expressions, and the use and reuse of anonymized or de-identified research data and registry data. Specific assessments should be made in each individual case. For example, determining what constitutes a public arena and when information is sufficiently anonymized or de-identified will often require the exercise of professional judgement.

In some cases, covert research is necessary, for example in order to uncover abuse of power or to protect the safety of research participants. Even in such cases, researchers must consider whether some information should be provided before and/or after the project. Researchers should also carefully assess whether the anticipated value of the research justifies the use of covert methods.

Exemptions from the Requirement for Consent 

Projects within medical and health research may, in certain cases, be granted an exemption from the requirement to obtain consent. Applications for prior approval of such projects are reviewed by the Regional Committees for Medical and Health Research Ethics (REK), which may grant such an exemption.

Following the amendments to the Health Research Act (expected to enter into force in 2026), the following conditions for exemption are set out in the new Section 14a: 

• The research entails no or only minimal risk or burden for participants. 
• It is difficult or impossible to obtain consent from a sufficient sample of the group being studied.
• The research is expected to have substantial societal value. 

All three conditions must be met. REK has already made similar assessments under the current legislation. Exemptions may, for example, be granted for research based on health data from many thousands of patients. Assessments will always be made on a case-by-case basis and will take into account the other provisions of the Health Research Act. REK may, for example, require that research participants be informed, even when an exemption from the requirement to obtain consent has been granted. 

«Passive Consent»

Providing consent to participate in research (research ethics consent) is an active act; nevertheless, the term «passive consent» is used in some contexts. Where the situation in fact concerns research conducted without consent or research carried out under an exemption from the requirement for consent, this should be clearly specified.

NESH has issued an advisory statement (Norwegian only) concerning a research project in which the use of passive consent was not recommended. At the same time, the committee noted that passive consent may be considered ethically justifiable in certain cases, provided that the requirements regarding information and the right to opt out have been met. 

Reduced or Absent Capacity to Consent 

Some individuals have reduced or absent capacity to consent. This means that they are unable to provide consent to participate in research on their own behalf. 

Persons with reduced or absent capacity to consent are not fully able to understand, assess, or decide what participation in research entails. This may, for example, be due to cognitive impairment resulting from intellectual disabilities or substance use, or from severe mental illness, acute illness, or disturbances of consciousness. In a research ethics context, these groups are considered particularly vulnerable. 

If such individuals are to participate in research, researchers must obtain consent from their legal guardian or parent(s). The participant cannot withdraw the consent/permission that has been given on their behalf, but they retain the right to refuse participation. For example, a legal guardian may consent to research on behalf of an individual, but the individual may still personally decline to participate. It should be remembered that participants themselves are also entitled to receive information about the research in a form adapted to their needs. 

Capacity to consent may vary over time. Researchers should therefore continuously assess participants’ ability to safeguard their own rights.  

Participants with conditions that vary over time, such as psychosis or substance-induced cognitive impairment, should be given the opportunity to confirm or withdraw consent when they are in a state in which they have capacity to consent. 

Research involving persons with reduced or absent capacity to consent requires special consideration: 

• The research must be necessary, meaning that it cannot be carried out with participants who have capacity to consent, 
• the research must be of benefit to the individuals being studied, and 
• the risk to participants must be negligible. 

This type of research is addressed in Sections 17 and 18 of the Health Research Act and in the Guidelines for Research Ethics in the Social Sciences and the Humanities. 

See also this discussion example from the Research Ethics Library: Research on the acute treatment of unconscious patients

Consent Involving Children 

Children who participate in research are entitled to special protection. The best interests of the child are the primary consideration.

The Guidelines for Research Ethics in the Social Sciences and the Humanities emphasize that research involving children requires ethical consent from both parents or guardians and the child. This is also a legal requirement. The child’s consent or agreement  must be based on the child’s ability to understand what participation entails. In exceptional circumstances, it may be ethically justifiable for children to participate in research without parental or guardian consent if this is in the child’s best interests. This may, for example, be relevant in situations involving conflicts of interest or a need for protection. Children also have the right to refuse participation, even if their parents or guardians have consented. 

In health research, individuals over the age of 16 have the right to provide consent on their own behalf, unless the research involves bodily interventions or clinical drug trials. Participants must also have decision-making capacity, meaning that they must understand what participation entails. In addition, several other conditions must be met before the research can commence. 

If a project extends over several years, children who reach the age at which they have capacity to consent should be asked again whether they wish to participate. 

Read more about children as research participants in this article from the Research Ethics Library. 

Watch an informational video for children about participation in research. 

Different Types of Consent

Broad Consent 

In health research, broad consent may be obtained. This means that research participants consent to the use of human biological material and health information for specified, broadly defined research purposes. Research participants who provide broad consent are entitled to receive regular information and have the right to withdraw their consent at any time.

Research based on broad consent and falling within the scope of the Health Research Act must be reviewed by REK. If REK determines that the analyses or purposes of a project fall outside the scope of the consent originally provided, new consent must be obtained.

Broad consent has been used particularly in research involving material stored in general research biobanks, medical research registries, and population-based health studies (for example, the Norwegian Mother, Father and Child Cohort Study (MoBa) and the Trøndelag Health Study (HUNT)). 

Dynamic Consent 

Dynamic consent is used in cases where there is a need for ongoing updates to consent. It involves an interactive process between the researcher and the participant in which participants are kept informed about changes to the research and about new research projects. Participants may update, modify, or withdraw their consent, and may approve or decline participation in new studies. This gives participants greater autonomy and may contribute to increased trust, but it also requires them to stay informed and actively engage with the project. In health research, digital communication solutions are often used to facilitate dynamic consent.

Further information: Broad consent versus dynamic consent in biobank research: Is passive participation an ethical problem? - PMC 

Collective Consent 

In research involving Indigenous Peoples and ethnic minorities, it is often necessary to obtain collective consent. Collective consent (the term “community consent” is also used) is a form of group-based approval allowing research to be conducted within a community or group. It is provided by a representative body. The process includes dialogue, community engagement, consultation, and culturally appropriate involvement. Collective consent is obtained in addition to – but never as a substitute for – individual consent.

In Norway, collective consent is an established requirement in Sami health research. 

Read more: Topic: Indigenous Peoples and National Minorities

How to Obtain Consent  Consent from research participants may be obtained in different ways. The most common approach is for participants to sign a consent form / participant information sheet.  The following are some suggestions for the design of such forms and information sheets.  Check whether your institution provides its own templates or guidance on what type of consent your research requires.  Use clear language: avoid academic, technical, or legal terminology unless it is explained; use short sentences; and adapt the language to the participant group (e.g. children, older adults, patients, speakers of minority languages, etc.).  The content of a consent form and participant information sheet will depend on both your research project and your field of research. The following are examples of information that a consent form may and should include:  Information about the research project or study, such as its purpose and duration.  Information about the responsible institution and, where relevant, how the research is funded and organized  Information about what participation in the research project or study involves, including methods (interviews, questionnaires, observation, examinations, etc.), scope (time commitment, number of interviews, etc.), what information or material will be collected, and how it will be collected (audio or video recordings, notes, electronic data, biological material, etc.).  Information that participation is voluntary and an explanation of how consent may be withdrawn. Information about possible disadvantages, burdens, or benefits associated with participation in the project, and how likely these are. Any follow-up support or contact available to participants after the study should also be described.  Information about how information and data will be stored and used, including who will have access to the data, where and for how long the data will be stored, and what types of information or data may be published.  Information about what will happen to the data and information when the research project has been completed.  Contact details for the responsible researcher and/or project manager  Consider whether renewed consent is needed if the project changes, for example through new research purposes, new collaborating partners, or new uses of data.  Examples of, and templates for, consent forms can be found here:  Information and Consent – REK Portal  Information for Participants in Research Projects – Sikt