USADA, reducing supplement risk through third-party certification

Guidance from the U.S. Anti-Doping Agency on lowering the risk that a supplement causes a positive test. It states that third-party certification, from schemes such as NSF Certified for Sport and, by the same logic, Informed Sport, significantly reduces but does not necessarily eliminate the chance of testing positive. Under the anti-doping principle of strict liability, an athlete who tests positive is responsible for the substance regardless of how it entered their body; even where a contaminated certified product is proven to be the source, a sanction (though possibly reduced) may still follow. The schemes differ in mechanics, with Informed Sport testing every batch against a large panel of substances while NSF uses variable-frequency testing against a similar panel, but neither is a guarantee. Authoritative body guidance rather than a study; useful for the strict-liability framing and for the point that certification reduces but does not eliminate the risk.