Consent involves deciding and becoming committed to the decision. Consent is the invisible act of evaluating information and making a decision, and the visible act of signifying the decision. Consent may be implied, such as by taking part in an interview or survey. Social research depends on participants’ active co-operation, such as to answer questions, and this could be taken as implied consent. People may, however, be afraid, or too embarrassed, to say ‘no’, unless they are given a respectful chance to refuse, withdraw, or agree to take part in some or all parts of the research.
In any research, there should be a time for people to be able to ask further questions, to decide, and to say ‘yes’ or ‘no’. Consent may be spoken, or written on a consent form. Participants should have a copy of the consent form and the information leaflet to keep.
Informed consent is specific, not blanket consent ‘to anything else the research might involve’. You should explain everything that you ask people to consent to. If the research plans are uncertain at first, you should say so. If the plans change, for example if new topics and questions are added, these should be explained and consent to the new plans should be requested. Most ethics committees require researchers to apply for approval again if the research involves any significant changes to the methods that were originally approved - including changes to methods of seeking consent.
Consent may be ’one-off’ to a single event. For longer studies, such as repeated observations, longitudinal or action research, or trials (including medical trials), or even during an interview or questionnaire, people have the right to change their mind, to withdraw, or to answer some questions but not others. This right should be made clear to them.
When you seek consent, you have to explain to potential participants exactly what will happen to the data that they provide, and you have to stick with that agreement. For example, if you seek consent for a one-off research interaction, it is not appropriate to go back later and ask for more data – that’s not what was agreed.
If you think you might want to do longitudinal work, but don’t yet know, then you should explain that it’s a possibility. If your data will be archived, you need to explain what that means, and give people the option of taking part, but refusing to have their data archived.
Archiving data and longitudinal work are potentially difficult in terms of the principle of fully informed consent, because you may, effectively, be asking participants to agree to something that is uncertain. See our section on consent to data archiving or data sharing.