Objective: To compare the variability of screening tests held at laboratories with the Unit for External Quality Control (UEQC), checking the frequency of cases that were discordant, false-positive, false-negative, unsatisfactory or that had a delay in clinical management and diagnostic agreement. Materials and Methods: The study analyzed 10,053 screening tests from January 2007 to December 2008, including all positive cases, all those that fall under unsatisfactory and at least 10% of negative screening tests. The magnitude of the agreement was analyzed using the kappa coefficient. Results: Out of the 10,053 cases analyzed, 7.59% were considered disagreeing, and it was estimated that 1.1% were false-negative. There was a delay in the clinical procedure regarding 2.44% cases. There were 2.82% of cases identified as false-positive and 1.24% as unsatisfactory. The diagnostic agreement was excellent (kappa = 0.81). The agreement of most laboratories concerning screening tests was classified as very good. The agreement of the sample adequacy was reasonable (kappa = 0.30) and the agreement regarding the representation of epithelia was considered excellent. Conclusion: Most laboratories showed very good agreement; however, it is worthy of note that to establish the standardization of diagnostic criteria, and enhance the accuracy of screening and improve the quality of cytopathology test results, it is necessary to perform external quality control.

Keywords:
Quality control, Cytology, Cervical screening
1.
Miller AB, Nazeer S, Fonn S, Brandup-Lukanow A, Rehman R, Cronje H, Sankaranarayanan R, Koroltchouk V, Syrjänen K, Singer A, Onsrud M: Report on consensus conference on cervical cancer screening and management. Int J Cancer 2000;86:440-447.
2.
Mandelblatt J, Lawrence W, Womack SM, Jacobson D, Yi B, Hwang YT, Gold K, Barter J, Shah K: Benefits and costs of using HPV testing to screen for cervical cancer. JAMA 2002;287:2372-2381.
3.
Franco R, Amaral RG, Montemor EBL, Montis DM, Morais SS, Zeferino LC: Factors associated with false-negative cervical cytopathological results. Rev Bras Ginecol Obstet 2006;28:479-485.
4.
Zahniser DJ, Sullivan PJ: Cytyc corporation. Acta Cytologica 1996;40:37-44.
5.
Gill GW: Blinded review of Papanicolaou smears. Cancer Cytopathol 2005;105:53-56.
6.
Takkanen J, Geagea A, Neiminen P, Anttila A: Quality improvement project in cervical cancer screening: practical measures for monitoring laboratory performance. Acta Obstet Gynecol Scand 2003;82:82-88.
7.
Ribeiro AA, Santos SCD, Silva SRRS, Nascimento MA, Fonsechi-Carvasan GA, Carneiro MAS, Rabelo-Santos M, Rabelo-Santos S: Endocervical component in conventional cervical smears: influence on detection of squamous cytologic abnormalities. Diagn Cytopathol 2007;35:209-212.
8.
Sood N, Singh V: Evaluation of 100% rapid rescreening of cervical smears. Indian J Pathol Microbiol 2009;52:495-497.
9.
Tavares SBN, Souza NLA, Manrique EJC, Albuquerque ZBP, Zeferino LC, Amaral RG: Comparison of the rapid prescreening, 10% random review, and clinical risk criteria as methods of internal quality control in cervical cytopathology. Cancer Cytopathol 2008;114:165-170.
10.
Branca M, Morosini P, Duca P, Verderio P, Giovagnoli MR, Riti MG, Leoncini L: Reliability and accuracy in reporting CIN in 14 laboratories: developing new indices of diagnostic variability in an interlaboratory study. Acta Cytol 1998;42:1370-1376.
11.
Ministry of Health, National Cancer Institute: Manual of Quality Management for Cytopathology Laboratories. Rio de Janeiro, 2012.
12.
Annabelle Farnsworth. Screening for the prevention of cervical cancer in the era of human papillomavirus vaccination: an Australian perspective. Acta Cytol 2011;55:307-312.
13.
Salvetto M, Sandiford P: External quality assurance for cervical cytology in developing countries. Experience in Peru and Nicaragua. Acta Cytol 2004;48:23-31.
14.
Pereira SMM, El Ramos D, Yamamoto LS, Shirata NK, di Loreto C, Ferraz MG, Longatto Filho L: External quality control of cervical cytopathologic and the reflex in the health public laboratory. DST-J bras Doenças Sex Transm 2006;18:172-177.
15.
Brazilian nomenclature for cervical cytology reports and guidelines. Rev Bras Ginecol Obstet 2006;28:486-504.
16.
Solomon D, Nayar R: Bethesda System for Reporting Cervical or Vaginal Cytologic Diagnoses, ed 2. Rio de Janeiro, Revinter, 2005.
17.
SAS/STAT software changes and enhancements through release 8.2. Cary, SAS Institute, Inc., 1999-2001.
18.
Landis JR, Koch GC: The measurement of observer agreement for categorical data. Biometrics 1977;33:159-174.
19.
Arbyn M: Detection of false negative Pap smears by rapid reviewing. Acta Cytol 2000;44:949- 957.
20.
Amaral RG, Zeferino LC, Hardy E, Westin MC, Martinez EZ, Montemor EB: Quality assurance in cervical smears: 100% rapid rescreening versus 10% random rescreening. Acta Cytol 2005;49:244-248.
21.
Sebastião APM, Noronha L, Scheffel DLH, Garcia MJ, Carvalho NS, Collaço LM, Bleggi-Torres LF: Study of undetermined atypias in relation to prevalence and disagreement percentile in cases of the Cervical Cancer Screening Program of Paraná, Brazil. J Bras Patol Med Lab 2004;40:431-438.
22.
Maeda MYS, Di Loreto C, Barreto E, Cavaliere MJ, Utagawa ML, Sakai YI, Corrêa RO, Adura PJD, Marzola VO: Siscolo-quality control system in the health public laboratories: preliminary study. J Bras Patol Med Lab 2004;40:425-429.
23.
Confortini M, Carozzi F, Dalla Palma P, Ghiringhello B, Parisio F, Prandi S, Ronco G, Ciatto S, Montanari G: Interlaboratory reproducibility of atypical squamous cells of undetermined significance report: a national survey. Cytopathology 2003;14:263-268.
24.
Gatscha RM, Abadi M, Babore S, Chhieng D, Miller MJ, Saigo PE: Smears diagnosed as ASCUS: interobserver variation and follow-up. Diagn Cytopathol 2001;25:138-140.
25.
Smith AE, Sherman ME, Scott DR, Tabbara SO, Dworkin L, Olson J, Thompson J, Faser C, Snell J, Schiffman M: Review of the Bethesda System Atlas does not improve reproducibility or accuracy in the classification of atypical squamous cells of undetermined significance smears. Cancer 2000;90:201-206.
26.
Juskevicius R, Zou KH, Cibas ES: An analysis of factors that influence the ASCUS/SIL ratio of pathologists. Am J Clin Pathol 2001;16:331-335.
27.
Stoler MH, Schifman M: Atypical squamous cells of undetermined significance-low-grade squamous intraepithelial lesion triage study (ALTS) group: interobserver reproducibility of cervical cytology and histology interpretations; realistic estimates from the ASUS-LSIL Triage Study. JAMA 2001;285:1500-1505.
28.
Cocchi V, Sintoni C, Carreti D, Sama D, Chiari U, Segala V, Delazer AL, Grilli N, Papaleo R, Ghirardini C, Bucchi L: External quality assurance in cervical/vaginal cytology: interlaboratory agreement in the Emiglia Romana region of Italy. Acta Cytol 1996;40:480-488.
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2013
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