Dear Carberry:
I think I may be able to answer a couple of your questions. I have not interviewed for this program (actually, I recently decided not to pursue medicine, so I guess I never will..more on that later) but this was my number one program/number one school after visiting there last summer.
Concerning the location of the Public Health school, as I understand it, if you do get accepted to this program then the majority of the classes you take for the MPH is through OHSU at the OHSU campus (so, yes, I believe they do have their own Public Health school). However, it is a requirement for all MD/MPH students to take 9 credit hours (I think, maybe a little more or less) at either Portland State University or the other university there in Portland (it escapes my mind at this moment). I believe the classes which you take away from OHSU at these other sites are required classes (i.e. core classes).
Concerning the timing of the year which you take off......unfortunately there is no cookie cutter plan for this. It is entirely up to the student and their advisor(s) to decide the most appropriate course load. From speaking with other MD/MPH students and graduates, it appears that the most common time to take the year off is in between 2nd and 3rd years of medical school in order to obtain the MPH. At OHSU, those who are admitted take a three week epidemiology course before the first quarter of Medical School, and then (on average) the MD/MPH student will take one MPH course each quarter in conjunction with the regular load of Medical School coursework until such a time when the student decides to pursue Public Health exclusively for the one year. I have spoken to former students of this degree (not necessarily from OHSU) who have taken the year off between 1st and 2nd years, and the general consensus is that you lose ties with your fellow classmates who you enter Medical School with and have to form new relationships with the incoming class. This doesn't seem so bad, but apparently it does bug people. Conversley, I have spoken to a couple of students who took the year of MPH coursework between 3rd and 4th year, and they stated this was probably the worst time to do it because of breaking the continuity of rotations. Again, you really just have to pick when the best time is for you. OHSU will be relaxed about whatever decision you make (or so it appears!).
Well Carberry, congratulations on your interview at OHSU (which goes for all of those above who have also been so lucky). I hope I have been helpful. Like I said earlier, I have recently decided to not pursue medicine as I think I would be extremely unhappy in the first two years of Medical School (as well as the next three years of my life as I had originaly planned to obtain second and third Bachelors in Biology and Psychology). I am really unhappy with the method of teaching and learning these upper science classes involve/require. Memorization for memorization's sake alone just does not sit well with me. But I digress. Good luck to you, Carberry, and to all of those applying in this cycle and coming years. And thank you to all those who have replied to my PM's concerning different topics....you really have been of great help. Best wishes...
Drew