I found a full page ad in a local Orlando newspaper, (not the regular paper, but we haven't been getting that lately). It's an interesting study. Here's the link
http://www.compassresearch.com/patients/current-studies/pain/cluster-headaches
The phone # on the link page is 407-841-0502 - Orlando Site
I am not able to participate in this study and I know nothing about it. I have zero knowledge of the study or the research company doing it.
It was pretty amazing to see a full page with giant letters saying "ARE CLUSTER HEADACHES GETTING TO YOUR HEAD?"