Here's a couple typical sorts of contracts:

http://www.compassionandsupport.org/...t_contract.pdf

http://www.oregon.gov/OSBN/pdfs/pain.pdf

Some states have laws requiring use of a contract, some don't but doctors in that state might use a contract anyway.

Here's what doctor's in Oregon consider: http://www.ohsu.edu/ahec/pain/painmanual.html