My Quora Answer to:
If you have been researching your symptoms on the Internet prior to a consultation with your family doctor, should you respect his/her superior knowledge and keep quiet about what you found?
Not at all. A well-informed patient is a good patient.
Let your doc know you have been doing research and what you found. At this point, let them think about it.
Physicians are trained to sort through all the signs, symptoms, test results, history, family history, etc. and come up with a “Differential Diagnosis,” which is a list of possible causes. The best docs I know come up with a lot of Differential Diagnoses (often just in their heads), and then narrow them down to the one diagnosis that explains everything best. Part of that process is using Occam's Razor: the most likely and best explanation is the single one that accounts for most, if not all, of the findings. As an aside, Occam also added that this excludes any “cause” that evokes supernatural intervention. In our Scientific Age, we don't even consider that anymore.
Back to your question. After throwing out there your research results, permit them to do what we do best. Their definitive diagnosis may or may not be the same as yours. Don't be offended if it isn't. Remember, they are applying their training and experiences.
Good Question.