Improving Informed Consent and Enhancing Recruitment for Research by Understanding Economic Behavior

Abstract

THE USE OF FINANCIAL COMPENSATION AS A RECRUITment tool in medical research continues to be debated on ethical grounds. Critics are against economic or market models, in which market forces determine payment practices, primarily because of the perceived undue inducement potential and on other grounds, including that participants from lower socioeconomic levels bear a disproportionate share of the research burden. Many of these arguments apply not only to the purest market model but to any model in which compensation to participants exceeds some threshold. We argue that economic forces operate regardless of how investigators choose to compensate participants. Thus, it is imperative that investigators acknowledge these forces and design compensation schemes that explicitly take economic forces into account. Economic principles predict that for otherwise undecided individuals, incentives serve as inducements, regardless of the compensation model used. If they did not, why would researchers pay research participants? In place of a model in which incentives do not substantially influence behavior, we describe a general positive model (describing how payments actually are determined) of costs and benefits factoring in the decision. This model is essentially the same as the market model rejected by Dickert and Grady, and the freedom of contract model proposed by Wilkinson and Moore, with an emphasis on nonpecuniary aspects of costs and benefits. Quite simply, we argue that individuals will participate in research if they think the benefit (including but not limited to monetary compensation) of doing so is greater than the cost. These costs and benefits vary across research projects, as well as across potential participants for any given project, as individuals perceive and value the costs and benefits of participation differently. Because monetary compensation is just one of many determinants of participation, regulating it alone will not prevent undue inducement. Several important implications flow from this model. First, research participants who fail to grasp the facts or implications of participation could be induced by low payment amounts: truly informed consent is thus integral to preventing undue inducement. Second, external validity, an important ethical dimension that depends on adequate and representative samples, will be limited unless compensation—monetary or otherwise—is recognized for what it is: a factor in real-world decision making. Third, financial gain is one of several factors in the research participation decision. By focusing on other factors, investigators may be able to enhance recruitment through other channels.