As a Sponsor trial leader I do not use social media such as Facebook or Twitter for my trials. We still use the old style of posters and paper flyers, etc. to spread the word. Also, through approved messages used in t.v. and radio commercials. I would suppose that social media would be a bit more difficult because people can add their opinion to what you are advertising for everyone to see. This is why it is very important to create Communication and Issue Management Plans.