Is is ethical to not compensate experiment participants who withdraw from the study?

Question

I do experiments on learning and instruction for my dissertation. They are almost no risks in participating in our studies--except maybe boredom since they tend to run for 30 minutes to 1 hour. We get a lot of unmotivated students who don't really take the experiment tasks seriously. But in spite of this, they never get penalized if they complete the experiment. That means they get their compensation (money or course credit) and we don't check their answers before they walk out of the lab.

However, what should I do if a student withdraws participation? Should they still be given monetary compensation or course credit? Would it be ethical to specify that they will only be compensated if they complete the study? This hasn't happened to me yet, but I am running an online study and it will be harder to keep track of whether participants really complete the study or not.

Answer 1

I have served on the IRB at two research institutions. The first question I would ask is what does your consent form state about how subjects are compensated if they withdraw? As of this point, if you do not indicate such in your consent form, you should compensate the subjects what you promised (whether they withdraw or not) until the end of the study or you amend your IRB protocol.

If this is a problem with a number of subjects, I suggest amending your IRB protocol. Is your study is minimal risk, an approval should (typically) not take a long amount of time. It is not uncommon to prorate compensation. For instance, those who initiate the study, but do not complete the study can receive half or some other fraction of the compensation. If your IRB approves this, it would still compensate all participants, but give additional incentive for completing the study.

You could amend so that those who withdraw from the study do not receive any compensation, but IRBs tend to frown upon this, so you may waste time waiting for the IRB to request a change to your amendment.

Whatever you do, you should not break protocol from what your IRB has already approved. You can also talk to a representative of the IRB and ask what they suggest for an amendment - this could approve your amendment request faster.

Answer 2

I don't see any ethical problem in not compensating people for work they don't do. However, you still have to frame the problem in a clear way in order to avoid frustration/litigations. Just write down explicitely that a student will receive compensation only if he/she completes the test.

As for motivating students to give you meaningful answer, that is a completely different story, and a much more complex one.

Answer 3

Providing course credit and monetary compensation are very different.

In terms of monetary compensation, the IRBs that I am aware of want to make sure that the money does not influence the subject's consent. Paying a subject $1000 for an hour of their time would probably be considered an undue inducement. Paying a subject $1000 for 100 hours of their time would be considered a reasonable reimbursement for their time and inconvenience. If, however, the payment is based on completing the study, then after they complete 99 hours of the study, they would effectively be paid $1000 for that last hour and the IRB is not going to be happy. For a 1 hour study, an IRB might not go either way; $10 or whatever the payment is, is never likely an undue inducement, but $10 is also not an unreasonable inconvenience allowance for 15 minutes. Whatever you decided, you need to get IRB approval.

Class credit is a whole different issue (cf. Are there ethical guidelines prohibiting penalties against potential research subjects who have not yet provided consent?) In my experience, students need to be given an alternative that provides the same learning objectives. In my old department we decided that that learning objective was not meet until the study was completed. Therefore, no class credit was given until the study, or alternative assignment, was completed. Again, whatever you decide, check with your IRB.