This patient support community is for discussions relating to thyroid issues, goiter, Graves disease, Hashimoto's Thyroiditis, Human Growth Hormone (HGH), hyperthyroid, hypothyroid, metabolism, parathyroid, pituitary gland, thyroiditis, and thyroid Stimulating Hormone (TSH).
This is a thyroid test that reportedly many fibromyalgia and CFS patients are failing. This test is also known as R-T3. Many Endocrinologists don't seem to be aware of this test.... but this is something that may be of interest to you if you have thyroid symptoms and/or thyroid problems.
http://www.holtorfmed.com/nss-folder/printable_pdf/thyroid/reverse_r3_%20thebest.pdf --- "Reverse T3 is the Best Measurement of Tissue Thyroid Levels"
http://thyroid.about.com/library/glossary/bl-reverset3.htm --- Reverse T3