They are calling to set up an in house visit by a doctor as part of their effort to understand their client base better. A few months ago we had the in house visit as I was curious what it was about. They come and complete and long survey that gives them a statistical data base for their client base so that they can make decisions about resource allocation, etc. It is 100% legitimate, it is done both anonymously and confidentially and has nothing to do with your personal health situation or treatment. If you support the health community getting best data so that they can improve their science, then you should respond. If you are paranoid then don’t do it.