title: Evaluation of a low-cost liquid-based Pap test in rural El Salvador: a split-sample study.
abstract: OBJECTIVE
  We sought to test the diagnostic efficacy of a low-cost, liquid-based cervical cytology that could be implemented in low-resource settings.
  
  
  METHODS
  A prospective, split-sample Pap study was performed in 595 women attending a cervical cancer screening clinic in rural El Salvador. Collected cervical samples were used to make a conventional Pap (cell sample directly to glass slide), whereas residual material was used to make the liquid-based sample using the ClearPrep method. Selected samples were tested from the residual sample of the liquid-based collection for the presence of high-risk Human papillomaviruses.
  
  
  RESULTS
  Of 595 patients, 570 were interpreted with the same diagnosis between the 2 methods (95.8% agreement). There were comparable numbers of unsatisfactory cases; however, ClearPrep significantly increased detection of low-grade squamous intraepithelial lesions and decreased the diagnoses of atypical squamous cells of undetermined significance. ClearPrep identified an equivalent number of high-grade squamous intraepithelial lesion cases as the conventional Pap. High-risk human papillomavirus was identified in all cases of high-grade squamous intraepithelial lesion, adenocarcinoma in situ, and cancer as well as in 78% of low-grade squamous intraepithelial lesions out of the residual fluid of the ClearPrep vials.
  
  
  CONCLUSIONS
  The low-cost ClearPrep Pap test demonstrated equivalent detection of squamous intraepithelial lesions when compared with the conventional Pap smear and demonstrated the potential for ancillary molecular testing. The test seems a viable option for implementation in low-resource settings.
authors.affiliation: 1Division of Cytopathology, Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA; 2Department of Obstetrics and Gynecology, University of Pittsburgh Medical Center/Basic Health International, Pittsburgh, PA; and 3Health International, San Salvador, El Salvador.
authors.forename: Jin
authors.initials: J
authors.lastname: Guo
authors.forename: Miriam
authors.initials: M
authors.lastname: Cremer
authors.forename: Mauricio
authors.initials: M
authors.lastname: Maza
authors.forename: Karla
authors.initials: K
authors.lastname: Alfaro
authors.forename: Juan C
authors.initials: JC
authors.lastname: Felix
mesh_terms: D000328:Adult; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis*; D055088:Early Detection of Cancer / Q000191:economics / Q000379:methods*; D004544:El Salvador; D005260:Female; D006801:Humans; D008875:Middle Aged; D065006:Papanicolaou Test / Q000191:economics / Q000379:methods*; D027383:Papillomaviridae / Q000302:isolation & purification; D011446:Prospective Studies; D012424:Rural Population; D012680:Sensitivity and Specificity; D002578:Uterine Cervical Dysplasia / Q000175:diagnosis*