This is a members' forum, so we're not doctors, but thyroid patients. However, there are times when I think many of us know a lot more about the issues than doctors do (we LISTEN to other patients). However, depending on the slant and scope of your project, our opinions may not be useful to you. Do you still want answers?
My comment would be that you really should get answers from some of our members with extensive personal experience and acquired knowledge from countless hours of searching for scientific studies to help understand about thyroid issues. I assure you they will be far different than most doctors' answers. Are you interested? If so, will you commit to giving us some feedback on what you learn and how you report findings? Also, is this project for a class or what? How will it be used?
As stated by the above posters, this is a patient forum, not doctors.
I also agree that many of the answers you would get here will differ from most doctors.
The answers to most of your questions are widely available via the internet, though you'd have to narrow down "thyroidism", and MedHelp does have policies regarding publishing information gathered on the web site.
You might try posting your question on the expert forum to get a doctor.
You might, also, want to take a look at the terms of use of the site and/or contact MedHelp for permission to conduct any type of study on the web site. You can scroll to the bottom of the page and look for the blue "contact us" button near the right hand of the page.
It took me weeks to get permission to compile a simple list of good thyroid doctors. I'm not sure they would allow the site to be used for research purposes.