The IRB may approve, request minor revisions, table or defer, or disapprove modification requests. The OSP staff will notify the researcher in writing of the decision of the IRB and of any changes required. Modification approval is not granted until all required changes have been made and submitted for review and approval. Once approved, the researcher is sent a modification approval letter by OSP staff. Upon receipt of the approval for the modification, the PI may initiate the modification.

The IRB may only approve modifications through the current approval expiration period, unless considered at the time of continuation review. Approval of a modification outside of the continuing review does not extend or otherwise change the expiration date of the IRB's approval for the project. IRB review of a modification outside of a continuing review requests does not constitute a continuing review. All researchers are still required to submit research projects for continuing review and approval on an annual basis.

Federal regulations require the prompt reporting by researchers of unanticipated problems that occur in the course of a current IRB approved research project and involve risk to subjects or others. Unanticipated problems may include unexpected adverse events. Unanticipated problems must be reported, within 48 hours, in a written report with a detailed description of the problems by the principal investigator.

OHRP provides guidance regarding the reporting of unanticipated problems or adverse events, including the following clarifications.

Unanticipated problems include any incident, experience, or outcome that meets all of the following criteria: