What is informed consent?
In almost all cases, human subjects research requires that investigators fully inform
participants of the risks, benefits, and procedures involved in a study. This applies
not only to physical studies such as exercise and diet studies, but surveys, interviews,
and observations as well. For ethical and legal reasons, an investigator must disclose
all the facts, risks, and discomforts that might be expected to influence an individual's
decision to willingly participate in a research protocol. For a complete list of the
requirements of an informed consent form, along with some examples, please see our guide here
What are the differences between consent and assent?
Both require you to disclose all risks, benefits, and facts of the study to the participants.
Put simply, adults are able to "consent," while minors can provide "assent." (Parents/guardians
must still give permission for minors to participate, but when minors are able to
understand the information regarding their participation, their assent is required
Do I always need to obtained informed consent from participants?
There are rare instances in which informed consent is not required. In such instances,
it might be appropriate for the subjects to waive consent or elements of consent.
A request for waiver of informed consent must be specifically justified by the researcher
in the proposal to the IRB.
What is a waiver of informed consent and when is it appropriate?
A waiver of informed consent could mean that some elements of required informed consent
are altered, or that consent is waived all together. The decision is ultimately up
to the IRB. You should never contact participants before IRB approval, even if just to gather
It might also be appropriate for a study to waiver child assent and parental permission.
The IRB is most likely to grant a waiver of informed consent if:
- The research involves no more than minimal risk
- The waiver of informed consent will not adversely affect the rights and welfare of
- It is not practicable to conduct the research without the waiver or alteration
- If your study requires waiver of consent (for example, studies of existing data or
that require deception). Please note, with such studies, it may be appropriate to
provide human subjects with pertinent information after their participation.
Do I still need an informed consent form if I am not collecting any identifying information?
Yes. Even in such studies where participants are "anonymous," consent is still required,
though it can be a modified form of consent. That is, all of the elements of consent
must be documented for the participant, but the signature line is replaced with a
statement informing the participant that completion and return of the survey is considered
implied consent. If there are any risks involved in the research, written consent
may be required. Such a distinction would need to be made by the IRB before the start
of the study.
What is implied consent?
Implied consent is actually a type of a waiver of documentation of informed consent.
The IRB may require that the researcher include a summary of the research to the participants,
- research purpose
- minimal risk assessment
- benefits to participants
- contact for questions regarding the research and participant rights
There are a number of instances where this type of consent is helpful, the most common
being an internet survey, as long as he survey does not ask for any identifiable information.
The introduction to the survey could be written in such a manner as to serve as the
"implied" informed consent form. The introduction would need to contain a statement
indicating that completion and return of the survey implies consent to participate
in the research.
Where can I find examples of consent forms?
Our consent form guide
has a good number of examples.
(This FAQ was adopted from Cornell University