One of Doctors Data patients excreted over 100%. I think her symporters (iodine absorbers) weren't absorbing and the test dose of 50 mg of Iodoral went right through her along with dietary iodine. Doctors Flechas and Shevin report this phenomenon. Dr. Shevin actually experienced this in his own loading tests, starting high, going lower, then higher.
The goal is to repair the symporters with the companion nutrients, particularly Vitamins B3 and B2 along with selenium and magnesium. Then retest after the patient has started absorbing. A lot of doctors aren't aware that if you're not absorbing you might test high, then lower three months later as the symporters rebuild, then higher where you get in the area you want to be.
Note: Doctors Data's results come out higher than FFP because they perform the test a little differently. You should stick with whatever lab you start with so your baseline makes sense months up the road.