A
principal investigator (PI) is the lead scientist or engineer for a particular well-defined science (or
other
clinical research) project, such as a laboratory study or
clinical trial.
In the context of federal funding from agencies such as the NIH or the NSF, the
principal investigator (PI)
is the person who takes direct responsibility for completion of a funded project, directing the
research
and reporting directly to the funding agency. For small projects (which might involve 1-5 people) the
principal investigator is typically the person who conceived of the investigation, but for larger projects
the PI may be selected by a team to obtain the best strategic advantage for the project.
In the context of a
clinical trial a
principal investigator (PI) may be an academic working with grants
from NIH or other funding agencies, or may be effectively a contractor for a pharmaceutical company working
on testing the safety and efficacy of new medicines.
A
principal investigator (PI) involved in a
clinical trial is responsible for ensuring that an investigation
is conducted according to the signed clinical trial protocol statement, the investigational plan, and
applicable regulations; for protecting the rights, safety, and welfare of subjects under the investigator's
care; and for the control of drugs under investigation.
The
principal investigator (PI) works at a clinical site which is a medical facility staffed with a medical
professionals and qualified for performing
clinical research. To be qualified as a clinical site, strict
regulations are to be adhered to. The foundations for these regulations are defined by the International
Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use
(ICH) and regulatory authorities, which set the guidelines for good clinical practice (GCP) at
clinical research sites.