Just a PSA (and no pun intended): in most places in the US these days, blood screening can be done without a doctor’s order and often more cheaply than what insurance will pay. Particularly if you pay direct, skip the doctor referral and order (and own) your own blood work. NOTE: this assumes you are not a nincompoop and enough of a research hound to understand what you’re ordering, how to understand the results in context, and ultimately return to a specialist for expert opinion. GP’s aren’t the gatekeepers they once were for blood tests.