title: The implementation of an external quality assurance method for point- of- care tests for HIV and syphilis in Tanzania.
abstract: BACKGROUND
  External quality assurance (EQA) programmes, which are routinely used in laboratories, have not been widely implemented for point-of- care tests (POCTs). A study was performed in ten health centres in Tanzania, to implement the use of dried blood spots (DBS) as an EQA method for HIV and syphilis (POCTs).
  
  
  METHODS
  DBS samples were collected for retesting at a reference laboratory and the results compared to the POCT results obtained at the clinic. In total, 2341 DBS samples were collected from 10 rural health facilities over a period of nine months, of which 92.5% were correctly collected and spotted.
  
  
  RESULTS
  The EQA method was easily implemented by healthcare workers under routine conditions in Northern Tanzania. For HIV, 967 out of 972 samples (99.5%) were concordant between DBS and POCT results. For syphilis, the sensitivity of syphilis tests varied between clinics with a median of 96% (25th and 75th quartile; 95-98%). The specificity of syphilis POCT was consistent compared to laboratory based test using DBS, with a median of 96% (25th and 75th quartiles; 95-98%).
  
  
  CONCLUSIONS
  Overall, the quality of testing varied at clinics and EQA results can be used to identify clinics where healthcare workers require remedial training, suggesting the necessity for stringent quality assurance programmes for POC testing. As Tanzania embarks on scaling up HIV and syphilis testing, DBS can be a useful and robust tool to monitor the quality of testing performed by healthcare workers and trigger corrective action to ensure accuracy of test results.
authors.affiliation: Leiden Cytology and Pathology Laboratory, Leiden, Netherlands. Pieter.smit@lshtm.ac.uk.
authors.forename: Pieter W
authors.initials: PW
authors.lastname: Smit
authors.forename: David
authors.initials: D
authors.lastname: Mabey
authors.forename: Thomas
authors.initials: T
authors.lastname: van der Vlis
authors.forename: Hans
authors.initials: H
authors.lastname: Korporaal
authors.forename: Julius
authors.initials: J
authors.lastname: Mngara
authors.forename: John
authors.initials: J
authors.lastname: Changalucha
authors.forename: Jim
authors.initials: J
authors.lastname: Todd
authors.forename: Rosanna W
authors.initials: RW
authors.lastname: Peeling
mesh_terms: D015492:AIDS Serodiagnosis / Q000592:standards*; D059788:Dried Blood Spot Testing / Q000592:standards; D015658:HIV Infections / Q000175:diagnosis*; D006801:Humans; D019095:Point-of-Care Systems / Q000592:standards*; D012424:Rural Population; D012680:Sensitivity and Specificity; D013587:Syphilis / Q000175:diagnosis*; D013588:Syphilis Serodiagnosis / Q000592:standards*; D013636:Tanzania