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What Is an Unexpected Event?

Cornell's Federalwide Assurance of Compliance with DHHS Regulations for the Protection of Human Subjects states that: "Research investigators will promptly report to the IRB any injuries or other unanticipated problems involving risks to human participants and others." (Section IV.A) These injuries and other unanticipated problems are also referred to as unexpected events. Unexpected events must be reported to the IRB on its Unexpected Event Form as well as by e-mail to the ORIA Director and IRB Coordinator. The IRB provides guidance (below) about what types of experiences in the course of a research study qualify as unexpected events and what constitutes prompt reporting. The form used to report unexpected events is listed on this web site.

Unexpected Events

An unexpected event is an occurrence or situation during the course of a research project that was 1) harmful to a participant taking part in the research, or 2) increased the probability of harm to participants taking part in the research.

Unexpected events vary in their seriousness. The death or serious injury of a research participant is a serious unexpected event. Negative, non life-threatening physical reactions to drugs administered in a study, or physical consequences from dietary manipulations (e.g. fainting) are also unexpected events that investigators must report to the IRB. Investigators must as well report negative, non life-threatening physical reactions in participants who have chronic diseases (e.g. heart conditions, diabetes). Unexpected accidents that occur in the course of a research project, for example, participants in an exercise study falling off an exercise bike or treadmill, should also be reported to the IRB. The failure of equipment during an experimental session should also be reported if it could have resulted in harm to a participant. (That is, investigators should demonstrate due diligence in maintaining their experimental equipment in working order.)

Social and behavioral interviews and studies that deal with sensitive issues may also give rise to unexpected events. Occasionally, research participants will become very upset because of the nature of questions. Another risk to participants in social and behavioral surveys is the release, even inadvertent, of their identities or personal information about them. All of these types of events qualify as unexpected events that investigators must report to the IRB.

Standards for prompt reporting of unexpected events

While investigators must report all unexpected events to the IRB, serious unexpected events (see definition above) must be reported immediately, with a formal report following within 24 hours of the event. All other events should be reported within two weeks. Prompt reporting is important. Unexpected events often require some modification of study procedures, protocols and/or informed consent. Any changes in procedures, protocols, and the informed consent process require the review and approval of the IRB.



IRB Main > IRB Forms > What Is an Unexpected Event?