"Freiwillig" ist alles nur eine Frage des Geldes

Zitat

The uptake of VMMC within 2 months was higher among men in the $US15.00 group (9.0%) and the $US8.75 group (6.6%) than among men in the $US2.50 group (1.9%) or the contr..

Compensation makes the cut:

http://link.springer.com/article/10.1007/s40274-014-1419-5