ring DIAC. I had the results with me and didn't know what to do and rang. They have my results online. DIAC has access to Medibanks database for visa applicants... I'm not sure if you are applying onshore or offshore, but if onshore and presuming your medical center processed the paperwork correctly, DIAC should be able to access your files over the net; hence you don't need to send that letter. However the lady on the phone advised me not to open the letter as in some cases they will want you to send that letter at a later date. Hope this info helped you. Ring DIAC for formal advice.