An external quality control survey (EQCS) for serum cortisol.
D003201:Computers; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D011786:Quality Control; D011933:Reagent Kits, Diagnostic / Q000592:standards; D013223:Statistics as Topic
D011933:Reagent Kits, Diagnostic; D006854:Hydrocortisone