Principles of consent: General principles and role of Participant Information Sheets
For consent to be considered both legal and ethical it must be:
- Given by a person with capacity;
- Voluntarily given, with no undue influence;
- Given by someone who has been adequately informed;
- A fair choice.
Although most adults are able to make decisions for themselves, there are some who will be judged not competent to do so. Young children are also usually considered not able to give consent themselves, however as they grow up and mature, most will develop capacity in time.
There are further legal and ethical considerations that you need to make before anyone not able to consent for themselves is included in your research. You will find additional guidance on this site.
Select the headings below to find out more:
General principles of consent for all studies:
The Participant Information Sheet (PIS) is not usually the only information provided to potential participants. The consent process usually also involves a conversation between one or more members of the research team and the potential participant. If the potential participant would like further information, they may also talk to an independent person.
It is known that you can improve understanding by providing information in a number of different formats (e.g. by providing a written PIS that supports a conversation).
Effective informing should enable potential participants to understand what is involved. Interactive questioning of potential participants within the consent process can also aid understanding and highlight areas that potential participants are misunderstanding without appearing condescending.
Consent is an iterative and on-going process. In many situations it is not necessary to obtain consent afresh at every stage of the study. However to aid understanding you might consider, in some circumstances, providing participants with information throughout their involvement in the study. This can be particularly important where new information becomes available that might impact on the risks or benefits that the study poses.
It can be helpful for the research team to encourage participants and family members to ask questions whenever they are uncertain about study procedures. Study summaries describing relevant phases of the study and ethical safeguards can be prepared to supplement information in the PIS.
You may decide that providing written information is not the best format to use at all, the use of other media may be more appropriate. For further guidance please refer to 'Style'
Consent does have to be indicated in some way: for many studies, consent can be written, oral or non-verbal. However, in Clinical Trials of Investigational Medicinal Products (CTIMPs) consent is not considered legal unless it is in writing.
The function of a consent form is to record the participant's decision, and to indicate that the process was conducted appropriately and with suitable discussion. A signature on a consent form does not in itself make consent valid. A person’s agreement with each statement contained in the consent form can be indicated by initialling or ticking boxes, or by providing the answers ‘yes’ or ‘no’ after each statement. The form itself is then signed by the parties involved in the consent conversation.
The Participant Information Sheet (PIS) should support the consent process by helping to ensure that all those who are invited to take part in a research study have been adequately informed. In most circumstances it should be used to support conversations with potential participants, rather than being the sole source of information being made available to them.
Effective informing should enable potential participants to make an appropriate decision that is right for them.
Potential participants must be able to understand the information given to them and consider this information in light of their own circumstances.
The PIS also provides potential participants with information to share with others who may be important to them, and who they would like to involve in the decision making process.
We strongly encourage testing your Participant Information Sheet (PIS) with an appropriate group of people (patients groups or other members of the public) can be very helpful in ensuring that:
- The language used is appropriate;
- The style and format of the PIS aids understanding;
- The PIS covers the risks and benefits that are relevant to your potential participants etc.
You do not need to obtain NHS Research Ethics Committee (REC) approval to test your PIS with patient groups or others.
Involving patient groups or the public in other ways can also be invaluable, for more information please refer to our 'Links' page.
When seeking consent from potential participants it is critical that you appropriately support them in making their decision. This includes that:
- You understand the protocol and the potential implications it may have on the people to be involved;
- You understand the alternatives that may be available to potential participants, this may include treatment alternatives;
- You have an ability to communicate effectively with potential participants, including explaining complex scientific / medical concepts;
- You appreciate how to optimise the voluntary nature of decision making, avoiding undue influence.
The Research Governance Framework of each UK nation identifies the principles of Good Clinical Practice (GCP) as describing best practice in all health and social / community care research. (Extract from Principles of ICH GCP).
In Clinical Trials of Investigational Medicinal Products (CTIMPs), UK law requires compliance with the principles of GCP described in legislation. (Extract from Principles in The Medicines for Human Use (Clinical Trials) Amendment Regulations 2006, No. 1928).
The International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use, Guideline for Good Clinical Practice (ICH GCP) provides further guidance on the information you might provide to potential participants as part of the consent process but this is not mandatory. The following is an extract of this guidance, for more information visit the ICH website. Adapt your Participant Information Sheet to your specific study (remember one size doesn't fit all).
- The study title and an invitation to participate;
- That the trial involves research;
- The purpose of the study;
- Why the potential subject has been chosen;
- The voluntary nature of participation and that subjects may withdraw from the trial at any time without penalty or loss of benefits to which they were otherwise entitled;
- The trial treatment(s) and the probability for random assignment to each treatment;
- The trial procedures to be followed, including all invasive procedures;
- Those aspects of the trial that are experimental;
- The alternative procedure(s) or course(s) of treatment that may be available to the subject and their important potential benefits and risks;
- The approximate number of subjects involved in the trial;
- The subject's responsibilities in the study, including the expected duration of their participation in the trial;
- The reasonably foreseeable risks or inconveniences to the subject, including specific risks of ionising radiation or pregnancy during the trial;
- The reasonably expected benefits. When there is no intended clinical benefit to the subject, they should be made aware of this;
- The subject or the subject's legally acceptable representative will be informed in a timely manner if information becomes available that may be relevant to the subject's willingness to continue participation in the trial;
- The foreseeable circumstances and/or reasons under which the subject's participation in the trial may be terminated;
- Care after the trial has stopped;
- The compensation and/or treatment available to the subject in the event of trial related injury;
- The person(s) to contact for further information regarding the trial and the rights of trial subjects, and whom to contact in the event of trial-related injury;
- Details of anticipated prorated payments and expenses, if any, for participating in the trial and any other arrangements for payment, including an explanation of how payment may be influenced by duration of participation or completion of diaries etc;
- Assurance that records identifying the subject will be kept confidential and, to the extent permitted by the applicable laws and/or regulations, will not be made publicly available. If the results of the trial are published, the subject's identity will remain confidential;
- What subjects should do if they have a problem or a complaint regarding the trial;
- Contact details are clearly stated.
It is important that you clearly present the voluntary nature of participation to potential participants during the consent process and in your Participant Information Sheet. Potential participants must be made aware that their care will not be affected in any way if they decide not to take part. You should also make it clear that they can choose to withdraw later, if they change their mind.
Consent must be given voluntarily: not under any form of duress or undue influence from health professionals, family or friends.
At the same time, there is evidence that potential participants value help in making their decision, often from their health care practitioner.
Ensuring that decisions are made freely is largely down to the training and experience of those taking consent.
Whenever possible, potential participants should be given time to consider fully the likely implications of the research before making a decision. Potential participants should not be rushed into decisions; they should have the opportunity to discuss their decision with family and friends if they wish.
There are no fixed guidelines for an appropriate amount of time to give potential participants to consider whether to take part in research. More burdensome studies may require a longer time for deliberation while consent for simple studies, such as questionnaire based studies, could be obtained more quickly. You must consider what length of time is appropriate for your study to ensure that consent is informed and voluntary.
General principles of consent for specific studies:
Deception is not commonly used in research in the UK, however some researchers (e.g. clinical psychologists) do use deception to explore issues in ways that would not be possible if complete disclosure of research objectives was made during the consent process.
When deception is deemed indispensable to a study the investigators must demonstrate to a Research Ethics Committee (REC) that:
- No other research method would suffice, and
- That advances could or are likely to result from the research.
In reaching a decision, the REC will carefully consider the purpose of, and justification for the deception as well as the specific details of the proposed study.
Deception is not permissible in cases in which the deception itself would disguise the possibility of greater than minimal risk to participants. Nothing should be withheld which, if divulged, would cause a reasonable person to refuse to participate.
You should consider whether and how participants will be informed of the deception once their participation has ended. Such 'debriefing', ordinarily entails explaining the reasons for the deception.
A participant who disapproves of having been deceived should be offered the opportunity to refuse to allow the investigator to use information thus obtained.
You should be aware that some participants may resent the deception. Any participant who is upset at having been deceived should be offered the opportunity to withdraw their data from the study.
There is an important distinction between deception and sham trials. In sham trials, the participant consents to be randomly allocated to an 'active' or a 'sham' procedure. In this situation, there is no deception as the participant has been informed that they may or may not get the 'active' treatment.