For the purpose of understanding if there is any quality difference between Quest Diagnostics and LabCorp, the answer is no, they both use the highest quality standards and machines.

However, if you’re asking about the price, our Quest prices are lower simply because our agreements with Quest are a bit different than those with Labcorp. 

Both Quest & Labcorp are America's largest clinical laboratories that we’ve partnered with for collection and processing of specimens for our customers since 2005.