Just to add to what RPedigo said, you know who the two other people in your group panel will be before you have to go into the interview with them. You should probably get to know them, just because it makes it more comfortable in the panel. Also, the group problem-solving question is medically relevant. Perhaps everybody already knows this, or just assumes, but since I went in thinking that the problem could be anything (read: guy with a boat, a chicken, a bag of rice and a wolf crossing a river) I just wanted to make sure that no one else did the same.
It was a little difficult trying to engage all three interviewers at the same time, and some of the questions seemed a little from left field, but overall the interview went fine. The interviews are closed file, so the only thing that they know about you is from your very brief introduction at the beginning. Make sure you include things you want to be asked about later. It was my first closed interview and for that reason I was a little caught off guard.
