Originally Posted by crewdawg

I'm guessing they'll say self selection bias. That said, I'm sure they could easily accomplish the same thing with an online survey emailed to the sampling groups, along with the phone calls. I don't mind them calling, they just have to have the ability to call back at a time that is better for me (which I've heard they will do). Just put the number in your contacts and it won't show up as spam.