Informed Consent

Informed consent (IC) is a fundamental legal and ethical tenet that requires three conditions for any valid intervention (diagnostic, therapeutic, preventive, or related to research): That the [Page 1146]participant (1) is provided with sufficient information to make an informed choice, (2) gives consent voluntarily, and (3) is competent to make a decision about involvement. Strictly speaking, requiring IC implies that no intervention or data gathering should take place until a potential participant has been informed about the purpose, nature, risks, and benefits of the intervention, and having acquired an adequate understanding of what the intervention entails has freely consented to it.

IC is predicated on the fundamental ethical principles of respect, beneficence (having the welfare of the participant as a goal), and nonmalfeasance (avoiding harm to the participant) as reflected in the protection of personal autonomy and privacy and defined variously in legal codes of nation states. Changes in decision-making capacity throughout the life span determine an individual’s ability for autonomous decision-making and have prompted regulations to enable treatment and research with persons in health-care settings who lack sufficient capacity.

The explicit recognition of respect for autonomy is reflected in the general turning away from the use of the term subject and the widespread adoption of the preferred term participant. This entry provides an overview of legal codes related to voluntary consent and then describes information disclosure and confidentiality, voluntariness, and competence in the consent process.

The first international document to require voluntary consent for research participation was the Nuremberg Code (1947). This instrument aimed to prevent experiments such as the ones performed on nonconsenting concentration camp prisoners during World War II from happening again and to extend the principle of requiring freely given consent to all forms of intervention.

Other important research ethics guidelines followed. Examples include the World Medical Association Declaration of Helsinki (adopted in 1964 and last amended in 2013) and the Council for International Organizations of Medical Sciences International Ethical Guidelines for Biomedical Research involving Human Subjects (2002). Guidelines were also issued by professional and research institutions in a number of countries such as the Belmont Report (1979) in the United States, the Tri-Council Policy Statement (2014) in Canada, and the Economic and Social Research Council Framework for Research Ethics in the United Kingdom (introduced in 2006).