RT Journal Article SR Electronic T1 Increasing the amount of payment to research subjects JF Journal of Medical Ethics JO J Med Ethics FD BMJ Publishing Group Ltd and Institute of Medical Ethics SP e14 OP e14 DO 10.1136/jme.2007.022699 VO 34 IS 9 A1 D B Resnick YR 2008 UL http://jme.bmj.com/content/34/9/e14.abstract AB This article discusses some ethical issues that can arise when researchers decide to increase the amount of payment offered to research subjects to boost enrollment. Would increasing the amount of payment be unfair to subjects who have already consented to participate in the study? This article considers how five different models of payment—the free market model, the wage payment model, the reimbursement model, the appreciation model, and the fair benefits model—would approach this issue. The article also considers several practical problems related to changing the amount of payment, including determining whether there is enough money in the budget to offer additional payments to subjects who have already enrolled, ascertaining how difficult it will be to re-contact subjects, and developing a plan of action for responding to subjects who find out they are receiving less money and demand an explanation.