RT Journal Article SR Electronic T1 The interference of heterophile antibodies in free thyroxine immunoassay JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP 52 OP 52 DO 10.7861/clinmedicine.19-2-s52 VO 19 IS Suppl 2 A1 Kate Tilley A1 Andrew Collier YR 2019 UL http://www.rcpjournals.org/content/19/Suppl_2/52.abstract