Do you mean like a short adventure that you might get off DriveThruRPG for free? If so, I'll read it and if it passes muster for me, I'll adjust difficulty of encounters as necessary and throw it at my players. No testing, really. Unless you consider that as a test of the material before using it in a future campaign.
Is that answering your question? Or do you have examples of other "resources" that you are specifically wondering about?