What is the Right Amount to Pay Clinical Trial Participants?

Kristina Lopienski
July 18th, 2017

Study volunteers are often paid for their participation in research, especially in the early phases of investigational drug, biologic or device development when health benefits to subjects are remote or non-existent. Both the payment amount and sequence of payments to clinical trial participants are occasionally debated, given the many ethical considerations. As there is no formula or straightforward answer, compensation varies widely depending on a number of factors.

What are the regulations for payments to participants?

There is no explicit guidance from the Office of Human Research Protections (OHRP) on payment to research participants. It is left at the federal regulations, which state in 45 CFR 46.116 that, “An investigator shall seek such consent only under circumstances that provide the prospective subject or the representative sufficient opportunity to consider whether or not to participate and that minimize the possibility of coercion or undue influence.”

Also, as a required element of informed consent, 45 CFR 46.116(a) states, “For research involving more than minimal risk, an explanation as to whether any compensation and an explanation as to whether any medical treatments are available if injury occurs and, if so, what they consist of, or where further information may be obtained.” One of OHRP’s tips on informed consent is, “If payment is given to defray the incurred expense for participation, it must not be coercive in amount or method of distribution.” OHRP states it’s acceptable to not pay participants as well

According to the FDA, payment should accrue as the study progresses so that a participant doesn’t have to finish the entire trial to receive compensation. In Payment to Research Subjects – Information Sheet Guidance for Institutional Review Boards and Clinical Investigators, it’s stated that, “Unless it creates undue inconvenience or a coercive practice, payment to subjects who withdraw from the study may be made at the time they would have completed the study (or completed a phase of the study) had they not withdrawn. While the entire payment should not be contingent upon completion of the entire study, payment of a small proportion as an incentive for completion of the study is acceptable to FDA, providing that such incentive is not coercive.

Payments that are too high constitute undue inducement. The amount should not be so large that it blinds an individual to the potential risks, impairs their judgment or causes them to lie about information that would disqualify them from participating. The decision to participate should not be influenced by the amount of money being offered, and volunteers should not see research participation as a way to make a living or regularly supplement their income. On the other hand, payments should not be so low that they are exploitative, attracting people who are desperate for money.

Related article: The New Standard for Reimbursing Subjects for Clinical Trial Participation

So, what payments amounts are acceptable?

Participants can be paid enough to make up for their inconvenience and time spent, and reimbursed for expenses incurred based on their participation, such as lost earnings, transportation, etc. Several models are proposed in What’s the price of a research subject? Approaches to payment for research participation (Dickert and Grady 1999). These include:

  • Market model: driven by the market rates in the participant’s location. Supply and demand of research volunteers drives the rate.
  • Wage-payment: providing a standard amount for time and effort on the part of the participant.
  • Reimbursement model: the participant provides receipts for the reimbursable activity such as mileage, parking, lodging or meals.
  • Appreciation model: the participant receives a token of appreciation given at the conclusion of the study.

What do IRBs look for in proposed payments to subjects? Certain approaches may work better than others for certain studies and sites. Some may use a combination of these models; others will use none. In Payment of clinical research subjects, Christine Grady offers this practical suggestion: “When deciding whether to offer payment to research participants in a study, investigators should take into account the nature of the study, the nature of participant contributions and vulnerabilities, institutional or organizational guidelines, and local societal and cultural norms. In the research proposal submitted to their IRB, investigators should describe the rationale for payment, how the dollar amount was calculated, and how and when payment will be made.”

At the time of initial review, the IRB will review everything to ensure nothing is coercive or presents undue influence. Most IRBs take the stance that payment should be commensurate with the time and intensity of the procedures that the participant is asked to commit. When assessing the risk-benefit ratio, IRBs should not consider payment a benefit to offset research risks when deciding to approve a study. This is because payment is not to be considered a benefit but rather a recruitment incentive. If there is a completion bonus for participation, the IRB should determine that the amount is reasonable and not so large as to unduly induce subjects to stay in the study when they would otherwise have withdrawn.

Once approved by the IRB, all payment information, including the amount and schedule of payment(s), as well as any possible costs to volunteers who participate in a study, are discussed with potential participants during the informed consent process, and documented in the informed consent form.

On-demand webinar: Best Practices for Participant-Centric Payments in Clinical Trials


There is no magic formula to calculate the “right” amount to pay research volunteers for their clinical trial participation. The average stipend and reimbursement amounts can vary widely across therapeutic areas. For like-studies, payments can differ protocol-to-protocol, and sometimes even site-to-site for the same protocol.

Without a standard or clear-cut answer, it can be difficult to decide an exact amount. However, by referring to the proper regulations and guidance documents, keeping ethical considerations in mind, and working closely with the IRB, you can determine an appropriate plan to pay study participants.

If you’re looking for a better way to pay your participants, learn more about Forte’s automated payment solution. Participant Payments helps clinical research sites, sponsors and CROs securely and immediately pay participants after each visit.