Medical Trials in Poland? How much do you get?

Hi what do people usually get for medical trials or psychological/sociological research projects, or egg donations in Poland?
Any experience?

I'm not sure if it's very popular in Poland; you are expected to donate your blood for free.

Depends how you classify free...you can get a paid day off work for donating blood, and free ham!

Free chocolate round our way, quite a lot, too. If you donate enough, you get a free bus pass.