Although the Federal Common Rule requires that informed consent documents include all material information, it does not specify the content of materials used to recruit human subjects. In particular, there is no federal regulation relating to how payment for research participation is to be advertised. Rather, the FDA has issued guidance, advising researchers not to emphasize payment information. In order to determine how IRBs have interpreted this guidance, we coded the policies of the top 100 institutions by receipt of NIH (...) funding, in order to determine whether they require, permit, or forbid researchers to disclose the amount of compensation in their recruitment materials. We found that the vast majority of institutions implicitly or explicitly permit such disclosures; however, there are a significant number of IRBs at each extreme, some discouraging or forbidding with others encouraging or mandating such disclosures. Such heterogeneity in local regulations suggests that IRB discretion may be imposing costs on human subjects and the scientific enterprise that outweigh the benefits. We suggest that this heterogeneity should be resolved towards a national consensus on permissibility. (shrink)