McCall McPherson explains why thyroid lab ranges marked "normal" vary wildly between labs and locations. Clinicians often trust the lab's flags without question, but those ranges aren't standardized. Your results might be flagged normal at one lab and abnormal at another.
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What if I told you there's no such thing as normal thyroid lab ranges? Because there really isn't. There is no true set standard that everyone agrees to and everyone conforms to. So depending on what lab you go to, depending on the location of the lab you go to, the normal range changes and varies. Your doctor really depends on what that lab says is normal and accepts largely, or most clinicians accept largely, that if the lab says it's as abnormal, it is. If they don't, it's normal. When guys like, that's so not okay. So technically, someone with the same lab marker, such as tsh, can be told by a doctor that their lab is normal because they just scan it and see that it's not in bold. And the next patient that same clinician sees can have the exact same same TSH number and it can be abnormal because maybe the lab has a little more narrow margins. This should not be the case. We need to have set standardized normals. We don't just need to be winging one of the most common health conditions in our country for treatment and diagnosis. So another reason to not believe that your thyroid labs are normal just because someone is telling you that they are.