A thyroid-stimulating immunoglobulin (TSI) test is a blood test that can help diagnose Graves’ disease, an autoimmune condition that causes an overactive thyroid. A TSI test measures levels of TSIs in ...

This article was reviewed by Felix Gussone, MD. If you’ve been feeling a bit more couch potato than go-getter lately, dragging through the day, snapping at people for no reason, or wondering where ...

The fibrinogen blood test is used to assess how well the protein called fibrinogen — also called coagulation factor I — performs in the blood and to measure its levels in your blood. The test is also ...