Unconditional compensation: reducing the costs of disagreement about compensation for research subjects.

A central requirement of research involving humans is that people who participate as subjects should do so voluntarily. We argue that disagreements about the effect of offers of compensation on subjects' ability to participate voluntarily are likely to persist and to have high social costs. We propose a novel compensation practice--to pay potential subjects whether or not they participate--and argue that its implementation in some regions, including the Eastern Mediterranean Region, may reduce disagreement and thus mitigate such costs. We outline a research programme for assessing the potential of this practice to reduce costs.