title: Potential for medical error: incorrectly completed request forms for thyroid function tests limit pathologists' advice to clinicians.
abstract: BACKGROUND
  Various publications have highlighted the significance of laboratory errors in the pre- and post-analytical phases and their impact on results. Thyroid-stimulating hormone (TSH) is a first-line thyroid function test and, if abnormal, reflex thyroxine (T4) or tri-iodothyronine (T3) testing is requested, depending on clinical and medication data provided. Interpretative comments are added to all TFT results.
  
  
  OBJECTIVE
  In view of the paucity of articles describing such errors, we audited laboratory request forms requesting thyroid function tests (TFT), received from primary care clinics and regional hospitals at our laboratory.
  
  
  METHODS
  We assessed 482 laboratory request forms for TFT from primary health care clinics for specific parameters.
  
  
  RESULTS
  A total of 482 forms were analysed. Medication/s used by the patient (74.5%) and doctor's contact number (65.1%) were the most commonly incomplete parameters. Of the 123 patients with medication details, 62 (50.4%) were on thyroxine.
  
  
  CONCLUSIONS
  There are few studies examining the frequency and impact of incomplete laboratory forms on laboratory errors, and even fewer studies examining interpretative comments accompanying clinical biochemistry results. We studied how pre-analytical errors in completing request forms may lead to incorrect interpretative comments and inappropriate reflex testing, and so influence the quality of the post-analytical phase.
authors.affiliation: Division of Chemical Pathology, National Health Laboratory Service, Tygerberg Hospital, Stellenbosch University, Tygerberg, W Cape. azemlin@sun.ac.za
authors.forename: Annalise E
authors.initials: AE
authors.lastname: Zemlin
authors.forename: Louise
authors.initials: L
authors.lastname: Nutt
authors.forename: Lesley J
authors.initials: LJ
authors.lastname: Burgess
authors.forename: Fredeline
authors.initials: F
authors.lastname: Eiman
authors.forename: Rajiv T
authors.initials: RT
authors.lastname: Erasmus
mesh_terms: D002624:Chemistry, Clinical; D019963:Clinical Chemistry Tests; D003951:Diagnostic Errors / Q000517:prevention & control*; D004282:Documentation / Q000592:standards*; D006801:Humans; D007755:Laboratories, Hospital / Q000592:standards*; D010338:Pathology, Clinical / Q000592:standards; D011785:Quality Assurance, Health Care; D012189:Retrospective Studies; D013548:Sweden; D013960:Thyroid Function Tests