Well here's the deal:
I was complete in mid-Sept, by mid January I had heard nothing, so I called and found out I was in the pre-int hold category. I had my PI here at UCSF write me a glowing (and I do mean glowing) letter of recommendation and send it to Tulane and a couple of other schools. The letter basically highlighted my research, my goals, work ethic, personal characteristics, etc.
I got an invite from SLU last week and called Tulane and asked when my file was to be re- reviewed and if I could coordinate an interview with SLU trip. She said that I should be reviewed again soon and that I should hear by the beginning of March. I was upset, I didn't want to fork over the dough to fly to the midwest just for one interview. I called SLU and told them to leave my invitation open indefinitely.
A woman at Tulane called me at work and said," Dean Pisano had just reviewed your file and said to offeran interview, are you still interested?" I was like , "Yes! Of course!". So I am off to NO in mid-March. SLU only interviews on Tuesdays and my Tulane interview is on Friday, so it looks like I am still not going to the SLU interview and withdrawing.
I guess the moral of the story is to have letters of recommendation sent highlighting what you have done since your application. If you really want to interview somewhere, show continued interest in the school.
Good luck! 🙂