Site growth

Adding sub investigators to grow site capacity

By TrialNotice · Updated
Principal investigator with a gray beard walking down a research clinic corridor with a coordinator in teal scrubs
Short answerSub investigators are physicians or other qualified staff who perform significant trial duties under the principal investigator, and those who make direct and significant contributions to the data are listed on Form FDA 1572. Adding them lets a site run more visits and studies, covers absences, and reduces dependence on a single PI, which sponsors and buyers both treat as a risk.

What does a sub investigator do?

Sub investigators perform delegated trial activities under the PI, such as assessments, eligibility review, and safety evaluations. FDA's Form 1572 guidance explains which research staff should be listed as sub investigators on the form (FDA). The PI remains responsible for the study and for supervising everyone on the delegation log.

Why add them?

  • Capacity: more physician hours for visits, assessments, and safety review.
  • Coverage: vacations and illness no longer stop a study.
  • Lower risk: buyers say overreliance on a single principal investigator constrains a site's value (Objective IBV).
  • A future PI pipeline: in 2020, 66% of PIs filed only one Form 1572 (Tufts CSDD); sub investigators who gain experience become the next PIs.

Who makes a good sub investigator?

  • Physicians in your practice or partner practices who treat the study population.
  • Nurse practitioners and physician assistants, where the protocol and sponsor allow.
  • Physicians interested in research but not ready to lead a study. In a Duke and FDA survey, almost half of one and done investigators wanted to do more trials but lacked opportunities (DaVita Clinical Research).

How do you bring them on?

  1. GCP training and protocol specific training.
  2. Delegation log entries for each task, signed by the PI.
  3. Listing on the 1572 where required, with current CVs and licenses.
  4. Supervised visits before working independently.

What else do sub investigators bring?

Their own patients and colleagues. A sub investigator who practices nearby brings a patient panel and a set of physician relationships into the study. Physicians refer less than 0.2% of their patients into trials today (Tufts CSDD); each new investigator widens the circle of doctors who hear about your studies from a peer.

Get your study in front of the right local physicians

TrialNotice builds a physician referral pipeline around one active study. We identify relevant local physicians within driving distance of your site, send study aligned direct mail, follow up by email and LinkedIn, track engagement with recipient level QR codes, and route warm responses into your site team's workflow.

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Sources

  1. FDA, "Frequently Asked Questions: Statement of Investigator (Form FDA 1572)"
  2. Objective Investment Banking and Valuation, "Valuation of Clinical Research Sites: What Buyers Look For"
  3. Applied Clinical Trials, "Tracking Change in the Global Investigative Site Landscape" (Tufts CSDD)
  4. DaVita Clinical Research, summary of the Duke and FDA investigator survey (Contemporary Clinical Trials Communications, 2017)
  5. Applied Clinical Trials, "Tufts CSDD Study Explores Low Recruitment Rates"

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