The Pros and Cons of Different PI Compensation Models

A frequent question asked in our industry is: "How much should we pay investigators for their work on a clinical trial, and what methodology should be used?"  While this question seems straightforward, it is quite complex. The amount and method by which you pay investigators can play a big role in the success, or lack thereof, of your site. 

Deciding which PI payment model is right for your site can be difficult, as there are numerous ways to compensate principle investigators for their work on a clinical trial. There are variations of PI payment models, but most fall into three categories: research salary, percentage of study budget, or hourly rate based on work performed. These three categories all have their strengths and weaknesses, but understanding the pros and cons can help you make more informed decisions regarding how you pay your investigators. Implementing the right model can lead to better success for your site.

The first model is research salary, and in this method, the principle investigator is paid a fixed salary for all the time that they spend working on clinical trials.

Pros of research salary model:

  • You and the PI will always know how much they are being paid
  • Requires less time with administrative tracking

Cons of research salary model:

  • If the volume of work for the PI falls, this method could prove very costly on a per hour basis
  • If the volume of work for the PI rises, the PI may feel they aren’t being compensated enough

The second model is percentage of study budget, and in this method, the PI is paid a fixed percentage of the final study budget for all their time spent working on the specific clinical trial.

Pros of percentage of study budget model:

  • You share the risk with the PI
  • You have a fixed PI expense percentage
  • Requires less time with administrative tracking

Cons of percentage of study budget model:

  • This model can be risky based upon the amount of time the PI works on the trial versus the actual dollars compensated
  • Protocol amendments can make this complex due to timing of when patients are enrolled

The third payment model is hourly rate based on work performed, and this payment method can be broken down into two unique methods based upon how you track the PI’s time. These two unique methods are actual time and estimated time. In the actual time model, the PI would physically fill out documentation describing the exact time spent for a specific study and the activity performed.

Pros of actual time model:

  • This method is the most compliant method, as you are compensating for actual documented spent on the trial
  • Allows sites to gather valuable insight about time and effort requirements to improve their budgets

Cons of actual time model:

  • PIs will need to spend a lot of time tracking their time and effort spent on a trial
  • Expense percentages can vary widely over different trial types
  • A robust tracking mechanism is needed to ensure proper payments

In the estimated time model, you must look at each activity the PI performs and create time allowances. 

Pros of estimated time model:

  • The estimated time method requires less paperwork for the PI than the actual time method
  • The estimated time method shows that a lot of thought was put into the compensation

Cons of estimated time model:

  • A robust tracking mechanism is required to ensure proper payments
  • Expense percentages can vary widely over different trial types

Another concept to consider is the technology to enable submission of documents, payments to the PI, and an auditable trail to ensure transparency. When it comes to PI payment models, there is no one correct answer. Finding out what payment model works for you and your principle investigators is crucial to the success of your site, and understanding the pros and cons of these payment models is the first step in the journey.