Deception in Research

There are times, particularly in behavioral research, when investigators will find it necessary to use deception or incomplete disclosure about the true purpose of the research. Deception and incomplete disclosure, however, should be used only when the research question cannot be answered without its use.

Deception in research can be defined as "purposely misleading participants by providing them with overt misdirection or false information about some aspect of the research." In contrast, incomplete disclosure can be defined as "the withholding of information regarding the true objectives of the research."

As the use of deception and incomplete disclosure restricts a subject's ability to make a truly informed decision regarding his/her participation in the research — one of the essential ethical concerns in human subjects research — a waiver or alteration of informed consent must be requested of the Institutional Review Board whenever deception or incomplete disclosure is planned.

For important and more detailed information regarding informed consent and the use of deception — including sample consent language — see the Informed Consent page

While the IRB understands that research involving deception or incomplete disclosure is necessary in some circumstances, it must look closely at its use before granting the necessary waiver or alteration of informed consent. When reviewing the use of deception or incomplete disclosure in human subjects research, the IRB must find all of the following criteria to be met:

  • The research involves no more than minimal risk to subjects.

  • The deception or incomplete disclosure will not adversely affect the rights and welfare of subjects.

  • The research could not practicably be carried out without the waiver or alteration of informed consent.

  • Whenever appropriate, the subjects will be debriefed at the earliest time feasible, preferably at the conclusion of the subject's participation in the research.

Generally speaking, deception and incomplete disclosure is not allowable if the subject would not have agreed to participate in the research had s/he been fully informed about the research prior to consenting to participate.


While debriefing is a useful tool in all human subjects research, it is an essential aspect of research involving the use of deception or incomplete disclosure.

The debriefing process involves the investigator providing the subject with the following:

  • A full explanation of the research.

  • A description of how the subject was deceived.

  • An explanation for the reasons why the research could not be conducted without the use of deception or incomplete disclosure.

  • The opportunity to have any questions answered regarding the research and their participation.

  • The opportunity for the subject to withdraw their data from the research.

  • An offer to provide the subject the results of the research once complete.

  • Depending on the level of risk involved in the deception, a list of resources the subject may utilize if s/he experiences any psychological trauma related to the deception or the research itself.

A debriefing and informed consent form must be signed by the subject and attached to the consent to participate. For detailed information regarding informed consent see the Informed Consent page

The debriefing process should occur as early as is feasible, preferably immediately after the subject's participation in the research is complete. There may be times when the investigator feels this will be detrimental to the research. In such situations, the investigator must send a debriefing document to the subjects at the conclusion of all subjects' participation in the research.

In rare instances the investigator may feel that debriefing may increase the risks to subjects (for example, if the subjects were selected for participation because of a negative characteristic). Such cases are reviewed carefully by the IRB, who must agree that debriefing may cause more harm than the deception itself.

Whenever deception or incomplete disclosure is proposed in a research protocol, the investigator must fully explain the necessity of the deception or incomplete disclosure; if appropriate, justify why immediate debriefing is not feasible; and include in the protocol a debriefing and informed consent form.