A propósito de los ensayos tipo IV

"Sponsors sometimes obscure the nature of their interest in phase IV studies from volunteers and investigators"...

Referencia:

London AJ, Kimmelman J, Carlisle B.Research ethics. Rethinking research ethics: the case of postmarketing trials. Science. 2012 May 4;336(6081):544-5.
PMID: 22556237