Principal Investigator

A principal investigator (PI) is the holder of an independent grant administered by a university and the lead researcher for the grant project, usually in the sciences, such as a laboratory study or a clinical trial. The phrase is also often used as a synonym for "head of the laboratory" or "research group leader." While the expression is common in the sciences, it is used widely for the person or persons who make final decisions and supervise funding and expenditures on a given research project.

In the context of United States federal funding from agencies such as the NIH or the NSF, the 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 PI 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 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.

There were 20,458 PIs on NIH R01 grants in US biomedical research in 2000. In 2013, this number has grown to 21,511. At the same time the success rate for an applicant to receive an R01 grant has gone down from 32% in 2000 to 17% in 2013.

The Association of Clinical Research Professionals (ACRP) provides a certification, specific to physician investigators/principal investigators (PIs). ACRP offers the designation "Certified Physician Investigator (CPI)".

In a study published by David Vulcano of Hospital Corporation of America, CPI certification has been shown to be a valid predictor of overall regulatory compliance based on comparing outcomes of FDA inspections between those that were CPI certified investigators to those that were not CPI certified. Specifically over the three year timeframe of the analysis, approximately 12% of FDA audits of investigators who were not CPI certified have resulted in an Official Action Indicated (OAI) classification, where there had been zero instances of OAI results among CPI certified investigators; this was statistically significant (p=<.001). Similarly, more than 50% of the inspections of CPI certified investigators yield No Action Indicated (NAI) results, compared to only 35% of investigators not certified by the Academy; this separation was also statistically significant (p=<.005). Other studies have had similar findings. Industry sponsors have considered CPI certification of investigators as an acceptable means of demonstrating competency in Good Clinical Practice.

...
Wikipedia