title: Internal quality control of semen analysis.
abstract: OBJECTIVE
  To test a scheme for quality control of semen analysis.
  
  
  METHODS
  The reproducibility of assessment of sperm concentration, motility, and morphology was obtained for the same sample measured by different technicians (between or intertechnician variation) and for different samples assessed by each technician with time (within or intratechnician variation).
  
  
  METHODS
  Andrology Laboratory.
  
  
  METHODS
  Semen samples were analyzed from all patients attending the clinic.
  
  
  METHODS
  None.
  
  
  METHODS
  Within technician and between technician coefficients of variation for concentration, motility, and morphology.
  
  
  RESULTS
  When 100 sperm were routinely assessed, both intratechnician variation, as assessed from the precision of duplicate measurements, and intertechnician variation revealed hyperbolic curves with increasing variation at low percentages (less than 20) of motile or morphological forms. When these low values were excluded, mean intratechnician variations were 5.0%, 8.4%, and 2.8% for concentration, motility, and morphology, respectively, and mean intertechnician variations were, respectively, 6.1%, 5.6%, and 5.6%. Similar mean intertechnician variation for morphology was obtained for repeated assessment of prestained (7.3%) or presmeared (5.9%) slides. The use of cryopreserved semen to monitor longitudinal changes in the technicians' assessments revealed variations of 8.1% to 12% in concentration and 9.7% to 14% in motility. Computing the monthly means for sperm concentration, motility, and morphology over a 4.5-year period revealed a marked reduction in percentage of normal morphological forms, unrelated to the sperm count or mean age of the men attending the clinic. This was shown to be a result of a shift in the assessment by technicians.
  
  
  CONCLUSIONS
  Quality control is necessary and possible in an andrology clinic.
authors.affiliation: Institute of Reproductive Medicine of the University, Münster, Germany.
authors.forename: T G
authors.initials: TG
authors.lastname: Cooper
authors.forename: J
authors.initials: J
authors.lastname: Neuwinger
authors.forename: S
authors.initials: S
authors.lastname: Bahrs
authors.forename: E
authors.initials: E
authors.lastname: Nieschlag
mesh_terms: D015925:Cryopreservation; D006801:Humans; D008297:Male; D011786:Quality Control; D012661:Semen / Q000502:physiology*; D012662:Semen Preservation; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology; D013094:Spermatozoa / Q000166:cytology / Q000502:physiology; D014944:World Health Organization