title: Assessment of the Validity and Reproducibility of the Pap Smear in Mexico: Necessity of a Paradigm Shift.
abstract: OBJECTIVE
  An assessment was performed of the quality of Pap readings in 19 cytology laboratories (CLs) in Mexico from the Cervical Cancer Screening Program.
  
  
  METHODS
  Nine CLs were affiliated with the Health Ministry (SSA), and ten were affiliated with the Mexican Social Security Institute (IMSS). Two sets of 200 cervical cytology specimens were prepared, one set for each institution. Fourteen percent of the specimens were positive and six were inappropriate for diagnosis (3%). All cervical cytology specimens were processed in the cytopathology laboratory at the General Hospital of Mexico, and histopathology was available for each positive case.
  
  
  RESULTS
  Thirty percent of the SSA reading centers had a sensitivity of at least 80%; however, not one of the ten IMSS laboratories evaluated reached this figure. Some reading centers had a sensitivity <65%, meaning that nearly half of the specimens with a cytology consistent with cervical neoplasm were not identified.
  
  
  CONCLUSIONS
  Given these results, it is a priority to effect a paradigm shift combining various screening tests to improve adherence to standards and enhanced cost-effectiveness of the early detection of cervicouterine cancer (CC) in Mexico.
authors.affiliation: Center for Research on Population Health, National Institute of Public Health, Cuernavaca, Mexico.
authors.forename: Elsa
authors.initials: E
authors.lastname: Yunes-Díaz
authors.affiliation: Center for Research on Population Health, National Institute of Public Health, Cuernavaca, Mexico.
authors.forename: Patricia Alonso-de
authors.initials: PA
authors.lastname: Ruiz
authors.affiliation: Center for Research on Population Health, National Institute of Public Health, Cuernavaca, Mexico. Electronic address: elazcano@insp.mx.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Lazcano-Ponce
mesh_terms: D064790:Clinical Laboratory Services / Q000191:economics / Q000592:standards; D003362:Cost-Benefit Analysis; D055088:Early Detection of Cancer / Q000191:economics / Q000592:standards; D005260:Female; D006801:Humans; D007753:Laboratories / Q000191:economics / Q000592:standards; D008800:Mexico; D065006:Papanicolaou Test / Q000191:economics / Q000592:standards*; D015203:Reproducibility of Results; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000191:economics / Q000517:prevention & control; D014626:Vaginal Smears / Q000191:economics / Q000592:standards*
keywords: Cervical cytology; Cervicouterine cancer; Pap smear