title: Target values and method evaluation in proficiency testing programs.
authors.forename: R
authors.initials: R
authors.lastname: Rej
authors.forename: C S
authors.initials: CS
authors.lastname: Norton-Wenzel
authors.forename: Z
authors.initials: Z
authors.lastname: Cao
mesh_terms: D019963:Clinical Chemistry Tests / Q000592:standards*; D006801:Humans; D011786:Quality Control; D012015:Reference Standards; D013974:Thyroxine / Q000097:blood
chemical_list: D013974:Thyroxine