From a sheer numbers perspective...the top ten medicine programs have roughly 400 spots available. If you arbitrarily (and I stress arbitrarily, don't miss the forest for the trees in this example) take the top 40 medical schools in the US, that affords 10 spots per medical school for matching into a top ten medicine program.
However, if you average the top 10 psych residencies to have roughly 10 spots each, thats 100 spots, or 2.5 med students taking from a pool of the top 40 medical schools. More realistically though, especially in psych where they are less prestige and numbers hungery as top medicine programs, you are "eligible" for the spots from any medical school especially if you have compelling experience or life stories that generally trump numbers (to a certain extent). Thus it averages even less.
Taking into account regional and program biases will skew these averages of course, and this was just an example. in addition, there is a top heavy effect that the harvards of the world would match all ten of their applicants into top programs regardless of their numbers and then it would trickle down, but you get what I mean. You should realize that based on the above consideration, and the fact that you imply that you are coming not from Harvard but a medical school in the 30-40 range of US News, in general...to match into a "top ten" name program (of which UCLA and UCSF both almost surely qualify), you should consider yourself one of the top 2 candidates in your medical school class for psychiatry.--not top two by numbers but top 2 by overall quality, however that is measured. And even then there is no guarantee.
If its any UC you are looking for, and you throw in the Stanford, USCs, and other west coast programs in there...then you are much better off and if you are from a UC yourself and interview well, then you are very likely, almost assured to find a spot in California. Don't fret. But work on selling yourself as a good candidate in as many ways as possible to maximize your chances.
best,
worriedwell
