When jrg00 says, "The only requirement is a passing score on USMLE step 1," I'm not sure exactly what s/he means, because then s/he says, "When applying to the fifth pathway program you are applying to New York Medical College and they require MCAT scores and transcripts from a U.S. university."
This is true. To do 5PW, you must meet all the prerequisites you would to get into a US med school, i.e., have the MCAT and certain classes. You also must have a bachelor's degree (unlike for US med school when you can enter with ~90 credits).
Questions on 5PW have been asked a lot here. By saying this I am not trying to discourage you from asking, only suggesting that you can get a lot of info if you do a search of the site for "5PW, 5th Pathway, fifth pathway," etc. Please post any other questions you have that aren't covered by the previous posts.
You should also go to the AMA's site ( <a href="http://www.ama-assn.org" target="_blank">http://www.ama-assn.org</a> ), and search for Fifth Pathway (under ECFMG certification section). And then there's the NYMC site: <a href="http://www.nymc.edu/depthome/fifth.asp" target="_blank">http://www.nymc.edu/depthome/fifth.asp</a>
Oh, almost forgot: you asked about the average USMLE score. I don't think data like that has ever been compiled. In order to get into 5PW, you must pass Step 1, so by definition, everyone who's admitted has higher than 182.