title: The External Quality Assessment Scheme (EQAS): Experiences of a medium sized accredited laboratory.
abstract: BACKGROUND
  We put forth our experiences of EQAS, analyzed the result discrepancies, reviewed the corrective actions and also put forth strategies for risk identification and prevention of potential errors in a medical laboratory.
  
  
  METHODS
  For hematology, EQAS samples - blood, peripheral and reticulocyte smears - were received quarterly every year. All the blood samples were processed on HMX hematology analyzer by Beckman-Coulter. For clinical chemistry, lyophilized samples were received and were processed on Siemens Dimension Xpand and RXL analyzers. For microbiology, EQAS samples were received quarterly every year as lyophilized strains along with smears and serological samples.
  
  
  RESULTS
  In hematology no outliers were noted for reticulocyte and peripheral smear examination. Only one outlier was noted for CBC. In clinical chemistry outliers (SDI ≥ 2) were noted in 7 samples (23 parameters) out of total 36 samples (756 parameters) processed. Thirteen of these parameters were analyzed as random errors, 3 as transcriptional errors and seven instances of systemic error were noted. In microbiology, one discrepancy was noted in isolate identification and in the grading of smears for AFB by Ziehl Neelsen stain.
  
  
  CONCLUSIONS
  EQAS along with IQC is a very important tool for maintaining optimal quality of services.
authors.affiliation: Advanced Center for Treatment Research and Education in Cancer, Tata Hospital, Kharghar, Navi Mumbai, India. Electronic address: vivekbhat2005@yahoo.com.
authors.forename: Vivek
authors.initials: V
authors.lastname: Bhat
authors.affiliation: Advanced Center for Treatment Research and Education in Cancer, Tata Hospital, Kharghar, Navi Mumbai, India.
authors.forename: Preeti
authors.initials: P
authors.lastname: Chavan
authors.affiliation: Advanced Center for Treatment Research and Education in Cancer, Tata Hospital, Kharghar, Navi Mumbai, India.
authors.forename: Chital
authors.initials: C
authors.lastname: Naresh
authors.affiliation: Advanced Center for Treatment Research and Education in Cancer, Tata Hospital, Kharghar, Navi Mumbai, India.
authors.forename: Pratik
authors.initials: P
authors.lastname: Poladia
mesh_terms: D002624:Chemistry, Clinical / Q000592:standards*; D006405:Hematology / Q000592:standards*; D006801:Humans; D007753:Laboratories / Q000592:standards*; D059021:Laboratory Proficiency Testing / Q000592:standards*; D012156:Reticulocytes / Q000737:chemistry
keywords: Assessment; Laboratory; Quality