Español
Questions About Cancer? 1-800-4-CANCER
  • Print
  • Facebook
  • Twitter
  • Google+
  • Pinterest

NCI Dictionary of Cancer Terms


principal investigator  listen  (PRIN-sih-pul in-VES-tih-GAY-ter)

  The person(s) in charge of a clinical trial or a scientific research grant. The principal investigator prepares and carries out the clinical trial protocol (plan for the study) or research paid for by the grant. The principal investigator also analyzes the data and reports the results of the trial or grant research. Also called PI.