HURRY, HURRY, HURRY! Is it all about the money?

Recently, I received a call from a veterinarian who wanted to be an investigator for an upcoming study. When I asked about his clinical trials experience, he told me, “I’ve got many studies under my belt.” As I probed further, it became clear that he had indeed worked on quite a few trials for several different sponsors.

Intrigued, I asked him why so many pharmaceutical companies had used him as an investigator. He replied, “Because I enroll quickly.” Always eager to learn new recruiting techniques, I pressed further. “I see my job as sales,” he continued. “I sell the owner on the study by telling them how much they’ll get paid. As soon as they hear that, they sign the consent form.”

As a student in nursing school, I learned that, without study participants, science would rarely become clinical reality. I also observed many different techniques for attracting patients to clinical trials. Emotional appeals, offers of free treatment, cash bonuses, and catchy ads all appeared with predictable regularity. However, the monetary comeons always left me feeling a little uneasy. As I progressed through my career, I soon realized that money played an important role in clinical trials.

Paying people to participate in clinical research is not a new concept. During the early nineteenth century, the American surgeon, William Beaumont, gave Alexis St. Martin free lodging, food, and clothing plus $150 to examine the contents of his stomach after a gunshot wound failed to heal.1 Today, both human and veterinary study subjects can expect quite a bit more for their participation. But at what point do these payments morph from fair compensation for pain, discomfort, or inconvenience to economic coercion or outright bribery?

There are no data in the literature indicating that payment of a certain amount impacts either a patient’s willingness to participate in a trial or their compliance once enrolled…or that a higher payment yields greater participation or compliance. Nor is there evidence that the amount of compensation is related to the patient’s understanding of the study’s objectives. So, is there a limit to how much you can pay a prospective subject to induce study participation?

The Official IRB Guidebook (used in human study review by Institutional Review Boards) defines inducement as undue and perhaps problematic if it is so “…attractive that [it can] blind prospective subjects to potential risks or impair their ability to exercise proper judgement.”2

When an owner is induced to enroll their pet in a clinical trial, they could be exposing the animal to serious harm. Even if the study investigator fully explains the study’s design and the test article’s risks and benefits, the offer of a large payment upon study completion could cloud the owner’s decision.

What if the study were placebo-controlled? Could a large payment induce an owner to more readily gamble that their pet would receive active test article? Or, what if the study indication were a condition for which there was no available treatment (approved or otherwise)? If the investigator convinced the owner to enroll their pet because its disease was rapidly progressing and there was no alternative treatment, would that be considered undue inducement?

These are complex questions. However, if the owner consent process does not distort the normal owner-veterinarian relationship, exploit the pet, inflate study benefits, mask test article risks, or violate confidentiality, any payment that is not overly generous is an appropriate and ethical inducement for study participation.


1Lederer, S. 1995. Subjected to science: human experimentation in American before the Second World War. The Johns Hopkins University Press. Baltimore, Maryland. p. 192.

2Office for Protection from Research Risks. 1993. IRB guidebook. Washington, DC, USA.