title: What do radioimmunoassay methods for free thyroxine using "unbound analogues" actually measure?
mesh_terms: D006801:Humans; D011485:Protein Binding; D011863:Radioimmunoassay; D013974:Thyroxine / Q000031:analogs & derivatives / Q000097:blood*
chemical_list: D013974:Thyroxine