Why Are We Still Talking About Compensating Research Participants?

By Lindsay McNair, Principal Consultant, Equipoise Consulting, and Ken Getz, Director, Tufts Center for the Study of Drug Development (CSDD)

Historically, paying research participants has been an issue treated with extreme caution; sponsors have worried about being accused of trying to unduly influence patients to enroll in studies, and IRBs leaned into the protectionism of wanting to make sure that participants were enrolling in studies for altruistic reasons rather than for financial gain.

Research ethicists revived conversations about compensation about 10 years ago. Much of the conversation was driven by article by Largent and Lynch, who pointed out that paying participants in research — not just reimbursement of expenses but compensation for time and effort and even incentive payments — was not inherently problematic when the risks of the research were already reasonable and potential participants were competent to make decisions for themselves.¹ Discussion has continued and expanded, and in May 2025, 65 research ethicists signed an open letter published in the American Journal of Bioethics, encouraging research oversight boards to shift the ethical questions from “Is this payment too much?” to “Is this payment enough?²

Costs Still Impede Trial Participation

The patient engagement movement and growing involvement of patient advocacy organizations also prompted a shift from looking at research participants as subjects to considering them to be partners in the research enterprise. Around the same time, more authors and organizations started to look carefully at barriers to research participation, fueled in part by increasing interest in clinical trial equity and the enrollment of underrepresented populations. A number of different groups began publishing quantitative data showing significant financial barriers to research participation.³ One study surveyed patients with cancer and found that of those who participated in a clinical trial, 47% reported that the additional expenses related to the study caused financial hardship, with 53% stating that the additional cost was $200 to $1,000 per month, and 13% of respondents reporting that they declined research participation because of the expected additional costs.⁴ One hundred and twenty-nine professional groups and patient advocacy organizations have recently collaborated on a letter encouraging the HHS Office of the Inspector General to create a safe harbor so that clinical trial sponsors have no concerns about anti-kickback regulations to prevent payment of participants’ clinical trial expenses.⁵

Regulators Remain Mostly Mum

The FDA had remained largely apart from this conversation, although it did update the guidance on Payment and Reimbursement to Research Subjects in 2018 to state that it generally did not consider reimbursement of expenses to be undue inducement. In its recent RFI released as part of Operation TrialBlazer, the FDA asked interested parties to submit data on many facets of participant payment, including its prevalence, study types, payment practices, and whether and how payment facilitates participation.⁶

New Data Doesn’t Give Much Clarity

Unfortunately, for some of the FDA requests, little or no quantitative data exists. For this reason, Tufts CSDD and DIA launched a new project in 2025. Following on an initial survey⁷, this project sought to gather data from multiple trial sponsors about study design, recruitment rates, participant retention, and compensation provided. The study aimed to characterize compensation practices overall and by subgroup, and to assess if there was an association between compensation practices and participant enrollment performance. Fourteen biopharma companies took part in the project, participating in guided interviews and contributing data from 42 clinical trials conducted across 46 countries. The data was presented and discussed at the DIA Global Annual Meeting in June 2025.

The interviews revealed wide variation in compensation practices, impacted by local practices and policies (country, region, and site), as well as by the participant population and condition being studied and protocol-specific requirements. The quantitative data showed that compensation structures were also complex, with a broad mix of expense reimbursement practices, payment for time and effort, incentive payments, and other support (e.g., providing standard care medications, third-party travel services, etc.). Payments were most often based on a per-visit schedule and were significantly higher in the U.S. compared to other regions. Payment administration was almost always outsourced or done in a hybrid model that included outsourcing but was handled in-house only 3% of the time. A comparison of payment information to recruitment rates and retention metrics (e.g., completion of the full study) found no associations.⁸

Not surprisingly, the results from this  study  are difficult to interpret. The analysis dataset included clinical trials ranging  from small studies in rare disease settings to large vaccine trials.  The trials were conducted in a wide variety of research settings among diverse research populations involving a variety of country/regional/local regulations and practices. 

Moreover, sponsors and CROs are customizing their recruitment and retention strategies to match the highly customized nature of the diseases under investigation and the executional clinical trial models — including remote and virtual visits — being utilized.

As such, empirically identifying standard practices that demonstrate impact and a clear financial return on recruitment investment is an uphill battle. But even in the absence of a financial rationale, compensating research participants is still the right thing to do.

Doing The Right Thing

The three ethical principles underlying the conduct of research as originally outlined in the Belmont Report are respect for persons, beneficence, and justice.

Compensating research participants can be justified by any of the three principles. The principle of respect for persons underlies the need to treat everyone as individuals with autonomy who can make decisions about the risks and benefits of research participation based on their own personal needs and values (unless they are in a vulnerable population), which includes allowing competent adults to consider the financial implications of research as part of their assessment, and recognizes that financial incentives may be part of that process as they are with so many other decisions that people make every day.

Beneficence means that we should be actively seeking to do good (not just “do no harm”) in our research practices and allowing people to benefit financially from participation in research may be part of that good. Certainly, preventing additional financial burden and stress due to research participation is inconsistent with beneficence.

The principle of justice, meaning that both the risks and benefits of research participation should be shared across populations and no group should either take all the burden or all the benefits, requires us to minimize the barriers to research participation, including financial barriers.

Over the next few years, the conversation about participant payment will continue. As we continue to look for more generalizable data on these practices, it will be important to remember that sometimes, we do things not because of the ROI or because the data tell us to, but because they are the right thing to do.

References:

1. Largent E and Lynch HF. Paying research participants: The outsized influence of “undue influence.” IRB: Ethics & Human Research 2017;39(4):1-9.
2. Abadie, R., Anderson, E., Eberts, J., Lynch, H. F., Fisher, J., Gelinas, L., Largent, E., and McNair, L. (2025). Pursuing Fair and Just Compensation for Research Participants: An Open Letter to the Research Ethics Community. The American Journal of Bioethics, 1–5. https://doi.org/10.1080/15265161.2025.2506328
3. Nipp RD, Powell E, Chabner B, Moy B. Recognizing the Financial Burden of Cancer Patients in Clinical Trials. Oncologist. 2015 Jun;20(6):572-5. doi: 10.1634/theoncologist.2015-0068. Epub 2015 May 18. PMID: 25986245; PMCID: PMC4571792.
4. Williams CP, Deng L, Caston NE, Gallagher K, Angove R, Pisu M, Azuero A, Arend R, Rocque GB. Understanding the financial cost of cancer clinical trial participation. Cancer Med. 2024 Apr;13(8):e7185. doi: 10.1002/cam4.7185. PMID: 38629264; PMCID: PMC11022148.
5. Community Support Letter for S.4440 Clinical Trial Modernization Act. https://www.fightcancer.org/policy-resources/community-support-letter-s4440-clinical-trial-modernization-act
6. Medicare and State Health Care Programs: Fraud and Abuse; Request for Information Regarding the Federal Anti-Kickback Statute and Beneficiary Inducements CMP
7. https://www.federalregister.gov/documents/2026/06/24/2026-12676/medicare-and-state-health-care-programs-fraud-and-abuse-request-for-information-regarding-the
8. Cooke DL, Fitzgerald F, McNair L, Pierce C, Whitaker S.  Breaking Financial Barriers: Making the Shift to Reasonable Compensation for Clinical Trial Participants. DIA Global Forum, December 2024
9. Bautista MP. Evidence Based Insights Informing Participant Compensation Strategies.  Presented at the DIA Global Annual Meeting, Philadelphia, PA.  June 15, 2026.

About The Authors:

Lindsay McNair, MD, is principal consultant at Equipoise Consulting.  From 2013 to 2023, Dr. McNair was chief medical officer for the WIRB-Copernicus Group (WCG). On the WCG IRB Executive Committee, she oversaw IRB member selection and training as well as IRB policy development and maintained regulatory/accreditation compliance. She provided consultation to biopharma and healthcare institutions on issues related to protocol design, regulatory compliance, human subject protection, and ethical policy development (pre-approval access, subject compensation). Dr. McNair is adjunct faculty at Boston University and teaches on the scientific design of clinical studies.  Dr. McNair is associate editor for the Journal of Empirical Research on Human Research Ethics and is in the NYU Compassionate Use Pre-Approval Access (CUPA) Working Group.  She has been part of the Human Subjects Review Board of the U.S. Environmental Protection Agency, working groups within Harvard’s Multi-Regional Clinical Trials (MRCT) program and in the Advancing Effective Research Ethics Oversight (AEREO) consortium.

Ken Getz is the executive director of the Tufts CSDD and a research professor at the Tufts University School of Medicine. He is an internationally recognized expert on pharmaceutical R&D management and execution, protocol design, contract service provider and investigative site management, eClinical technology and data usage, and patient engagement. A well-known speaker at conferences, symposia, universities, investor meetings, and corporations, Ken has published extensively in peer-reviewed journals, books, and the trade press. He holds board appointments in the private and public sectors. He received his MBA from Northwestern University and his bachelor’s degree from Brandeis University. Ken is also the chairman of CISCRP — a nonprofit organization that he founded to educate and raise public and patient awareness of the clinical research enterprise — and the founder of CenterWatch, a leading publisher in the clinical trials industry and one of several businesses that he has sold.