title: Analytical performance evaluation of a high-volume hematology laboratory utilizing sigma metrics as standard of excellence.
abstract: BACKGROUND
  Around two-thirds of important clinical decisions about the management of patients are based on laboratory test results. Clinical laboratories are required to adopt quality control (QC) measures to ensure provision of accurate and precise results. Six sigma is a statistical tool, which provides opportunity to assess performance at the highest level of excellence. The purpose of this study was to assess performance of our hematological parameters on sigma scale in order to identify gaps and hence areas of improvement in patient care.
  
  
  METHODS
  Twelve analytes included in the study were hemoglobin (Hb), hematocrit (Hct), red blood cell count (RBC), mean corpuscular volume (MCV), red cell distribution width (RDW), total leukocyte count (TLC) with percentages of neutrophils (Neutr%) and lymphocytes (Lymph %), platelet count (Plt), mean platelet volume (MPV), prothrombin time (PT), and fibrinogen (Fbg). Internal quality control data and external quality assurance survey results were utilized for the calculation of sigma metrics for each analyte.
  
  
  RESULTS
  Acceptable sigma value of ≥3 was obtained for the majority of the analytes included in the analysis. MCV, Plt, and Fbg achieved value of <3 for level 1 (low abnormal) control. PT performed poorly on both level 1 and 2 controls with sigma value of <3.
  
  
  CONCLUSIONS
  Despite acceptable conventional QC tools, application of sigma metrics can identify analytical deficits and hence prospects for the improvement in clinical laboratories.
authors: Section of Hematology, Department of Pathology and Laboratory Medicine, Aga Khan University Hospital, Karachi, Pakistan.
authors: M S
authors: MS
authors: Shaikh
authors: Section of Hematology, Department of Pathology and Laboratory Medicine, Aga Khan University Hospital, Karachi, Pakistan.
authors: B
authors: B
authors: Moiz
mesh_terms: D064790:Clinical Laboratory Services / Q000592:standards*; D006403:Hematologic Tests / Q000379:methods / Q000592:standards*; D006801:Humans; D011786:Quality Control; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017749:Total Quality Management
keywords: Hematology; clinical laboratory; health care; quality control; sigma