Recently I have had some interesting discussions with my students in the Research Methods class about the use of incentives in research studies. We all know that incentives help recruit and retain study participants, but some people consider them a form of undue influence or corruption of judgment, which may lead to biased data and damage the validity of the study. This makes me wonder, in what circumstances incentives are just innocuous incentives, and in what circumstances they morph into a temptation that attracts people to participate in a study against their better judgment?
I heard a program on the radio the other day, and it was about Amazon.com’s exclusive invitation-only club called Vine. Members of Vine are the top-reviewers of Amazon, and Amazon sends them freebies ranging from earbuds to color printers. A professor from NYU believes that such a program would lead to biased product reviews, because “as humans we are hard-wired to give in to this sort of, you know, enticement where if you continuously get things for free, then you’re more likely to be biased positively than biased negatively”. However, a spokesperson from Amazon claimed that Vine reviewers are not positively biased – they actually give lower star ratings that the average reviewers on the site. Her theory is that “it’s because they take that role so seriously to give as much sort of unbiased perspective on reviewing that product”.
This was quite an interesting story. So I dug around a bit more to find some scholarly literature about using incentives in research studies, and stumbled upon this article “Ethics in Human Subjects Research: Do Incentives Matter?” The authors stated “incentives become problematic when conjoined with the following factors, singly or in combination with one another: where the subject is in a dependency relationship with the researcher, where the risks are particularly high, where the research is degrading, where the participant will only consent if the incentive is relatively large because the participant’s aversion to the study is strong, and where the aversion is a principled one”.
This article is quite helpful to inform decisions concerning incentives. But we first have to be able to offer incentives before we consider how to offer them. I guess this means I have to get back to grant-writing now. 🙂









