Emily A. Largent, Ezekiel J. Emanuel, and Holly Fernandez Lynch write:
"Offers of payment made in exchange for research participation are common. And yet they are often regarded as, at best, a 'necessary evil.' This is odd. In most nonresearch contexts, people find payment for goods and services unproblematic. Indeed, when goods and services are not intended as gifts, failure to pay for them is a problem; we call it theft. Why should payments made in the context of research participation be of particular ethical concern?"