Gluten Free Watchdog is an organization run by Tricia Thompson, MS, RD.  They send out select foods for testing and each sample is tested in duplicate using the standard sandwich R5 ELISA (R7001 Ridascreen Gliadin) and extracted with the cocktail solution (Art. No. R7006, official R5-Mendez method).  These are some of the most accurate gluten screening tests known to man.

Gluten Free Watchdog has found some alarming trends:
As of February 15, 2012 Gluten Free Watchdog has tested 150 packages of gluten-free labeled food (representing 50 different products). Each sample was tested in duplicate (to guard against laboratory error and ensure that the sample tested is homogenized) for a total of 300 extractions.

Of the 300 extractions:
268 (89%) tested less than 5 ppm gluten; Safe
15 (5%) tested between 5 and 20 ppm gluten (range 6-18 ppm);  Caution!
17 (6%) tested greater than 20 ppm gluten (range 26-100+ ppm);  Extreme Danger!

For $4.99 a month you can support this organization and see their test results. I think it’s well worth the money (we’ve already tossed out some things we had been buying). Just because something is labeled gluten free, it may or may not actually be.  Inform yourself and beware of anything you purchase!