ICH E6(R3) – A person responsible for the conduct of the clinical trial, including the trial participants for whom that person has responsibility during the conduct of the trial. If a trial is conducted by a team of individuals, the investigator is the responsible leader of the team and may be called the principal investigator. Where an investigator/institution is referenced in this guideline, it describes expectations that may be applicable to the investigator and/or the institution in some regions. Where required by the applicable regulatory requirements, the “investigator” should be read as “investigator and/or the institution.”
CDISC-Gloss – An individual who conducts a clinical investigation (i.e., under whose immediate direction the test article is administered or dispensed to, or used involving a subject, or, in the event of an investigation conducted by a team of individuals, is the responsible leader of that team). [21 CFR 50.3] See also sponsor-investigator, site investigator, principal investigator, coordinating investigator, sub-investigator.