Endangered Species?

A fairly common study request these days seems to be an online survey among 500 U.S. males, age 21-64, with about a 20% category incidence. When we send this request to the various online panel providers, I am shocked to find many of them tell me they cannot fill the request.

I know males are more difficult to interview, but do the math. Taking a 20% incidence into account, assuming a 50% drop-out rate (which is much higher than typical, but these are stubborn American males), and a 5% click-through rate, the panel would need to send invitations to 100,000 males. Given that most companies boast panels in the millions, this doesn’t seem like that difficult of a request.

So what’s the problem? Is the active panel membership significantly smaller than what the panel books tell us? Is the click-through rate even worse than 5% (which I already consider pretty dismal)? Are male respondents in such demand that they are over-interviewed? Are incentives too low?

Someone please help me. The math just doesn’t add up.