I posted this in another thread, but think it's worthy of its own thread with all the PED assumptions and accusations. When we talk about PED testing, you have to consider the type of testing. There are 3 general categories, and "tbaumann" helped me expand the details (see below). When someone says "Fighter A" never failed a test," you have to consider the type of testing they've had. And you can only compare fighters tested in the same categories. If you say "Randy Couture/Fedor/etc." never tested positive so they fought clean," realize they've only been under the first 2 categories of testing. It's not fair to compare them to fighters tested under USADA. Compare apples with apples, not with oranges. Below are the categories: Early UFC, Pride, current Japan and Russia: no testing/anything goes Mid-UFC, Strikeforce, current Bellator: In most cases, highly predictable/scheduled baseline testing. As long as you avoid substances with long detection periods, and stop using within the detection window, you will test clean. Commissions only test for a relatively narrow spectrum of substances, and do not test for peptides, gh/epo, pct drugs, etc. USADA: Strictest testing. Utilization of CIR testing, biological passport, and other advanced methods to catch cheaters. Test for a broad spectrum of substances including peptides, gh/epo, pct drugs, etc. Many fighters tested clean for 10+ years in the UFC/SF/etc. but were caught under USADA.