title: Internal Quality Control Practices in Coagulation Laboratories: recommendations based on a patterns-of-practice survey.
abstract: BACKGROUND
  Internal quality control (IQC) procedures are crucial for ensuring accurate patient test results. The IQMH Centre for Proficiency Testing conducted a web-based survey to gather information on the current IQC practices in coagulation testing.
  
  
  METHODS
  A questionnaire was distributed to 174 Ontario laboratories licensed to perform prothrombin time (PT) and activated partial thromboplastin time (APTT).
  
  
  RESULTS
  All laboratories reported using two levels of commercial QC (CQC); 12% incorporate pooled patient plasma into their IQC program; >68% run CQC at the beginning of each shift; 56% following maintenance, with reagent changes, during a shift, or with every repeat sample; 6% only run CQC at the beginning of the day and 25% when the instruments have been idle for a defined period of time. IQC run frequency was determined by manufacturer recommendations (71%) but also influenced by the stability of test (27%), clinical impact of an incorrect test result (25%), and sample's batch number (10%). IQC was monitored using preset limits based on standard deviation (66%), precision goals (46%), or allowable performance limits (36%). 95% use multirules. Failure actions include repeating the IQC (90%) and reporting patient results; if repeat passes, 42% perform repeat analysis of all patient samples from last acceptable IQC.
  
  
  CONCLUSIONS
  Variability exists in coagulation IQC practices among Ontario clinical laboratories. The recommendations presented here would be useful in encouraging standardized IQC practices.
authors.affiliation: Institute for Quality Management in Healthcare (IQMH), Toronto, ON, Canada.
authors.forename: A
authors.initials: A
authors.lastname: McFarlane
authors.affiliation: Institute for Quality Management in Healthcare (IQMH), Toronto, ON, Canada.
authors.forename: B
authors.initials: B
authors.lastname: Aslan
authors.affiliation: Institute for Quality Management in Healthcare (IQMH), Toronto, ON, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Raby
authors.affiliation: Hamilton Regional Laboratory Medicine Program, Hamilton, ON, Canada.
authors.forename: K A
authors.initials: KA
authors.lastname: Moffat
authors.affiliation: Sunnybrook Health Sciences Centre and University Health Network, Toronto, ON, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Selby
authors.affiliation: Ottawa Hospital-General Campus, Ottawa, ON, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Padmore
mesh_terms: D001780:Blood Coagulation Tests / Q000592:standards*; D006801:Humans; D020407:Internet; D007753:Laboratories / Q000592:standards*; D059021:Laboratory Proficiency Testing; D009864:Ontario; D011364:Professional Practice / Q000592:standards; D011786:Quality Control; D011795:Surveys and Questionnaires
keywords: Coagulation; hemostasis; laboratory practice; quality control