Why All Thyroid Function Tests Suck? #ThyroidTest , I hate to be the bearer of bad news. But if I don’t tell you, then no one else will. I’m here to tell you that your doctor and the medical profession in general is more confused than ever regarding hypothyroidism, healthy thyroid function, and thyroid testing. Here is what you need to know about the common types of thyroid function tests and why they don’t work.