For an individual to participate in a research project, they must provide informed consent. This is a principle that is central to the ethical undertaking of all biomedical research, and one that is enshrined in global human research guidelines and regulations via the Nuremberg Code (1947) and Declaration of Helsinki (World Medical Association, 1964; most recent update, 2013). Informed consent as a process is one in which both research participant and researcher (or the person taking consent if different from the researcher) need to take an active role. It can be broken down into 5 main steps:
Competency relates to an individual's ability to provide informed consent (competency is a legal definition) and if individuals are deemed to be non-competent then they will be unable to provide consent. They can, however, have the power of consent delegated to another individual such as a family member or a carer.
To enable individuals to give fully informed consent, they must be fully apraised of all aspects of the study. This is the element of disclosure. All elements of the study process, including all potential risks and benefits, must be disclosed at this point, and the individual given the opportunity to ask questions.
Providing participants with all the information is only one aspect of the informing process; the person taking consent must also assess whether the individual in question understands what they are signing up to. This ensures they have read the information, and know what their role in the study will be and what it entails.
Individuals must provide consent by their own free will, free from coercion and any other influences. It is up to the individual taking consent to determine that the persons providing consent are doing so on their own behalf with no undue influence from other parties or external factors.
The provision of consent is usually the final step in this process. This is normally provided in a written form alongside the signature of the researcher (or other individual who is taking consent), although other methods can be used in cases where individuals are unable to write (for example, use of thumbprints).
Consent is, however, not always the final step, for two main reasons:
- Should new information regarding the study become available, this will need to be communicated to the study participants and may require re-consenting if the changes are deemed to be significant.
- Study participants may withdraw from a study at any point, in which case their consent is no longer valid.