Reproducibility study of cervical cytopathology in Mexico: a need for regulation and professional accreditation.
Due to the high rate of false negative results in diagnosis of cervical cytopathology, in many countries its practice has been transformed through the application of several interventions aimed at medical regulation to improve diagnostic accuracy. Diagnostic reproducibility of gynecological cytopathology was evaluated in a series of 20 cytology specimens [Papanicolaou (Pap)] and 20 cervical biopsy. (CB) studies in different clinical stages, during 1994. The observation unit consisted of 30 pathologists who observed 2 groups of 20 Pap and 20 CB specimens. The standard was a cytopathologist certified by the Pathological Anatomy Council of Mexico. Intraclass reproducibility in gynecological cytopathology is low in Mexico. In a group analysis, concordance increased as clinical status of the cervical lesion increased. For moderate dysplasia, concordance in Pap was kappa = 0.04, compared to 0.23 in CB. Concordance of diagnosis of invasive cancer was 0.29 for Pap and 0.64 for CB. Using weighted kappa at the individual level for all possible diagnoses, concordance varied from 0.29 to 0.59 for Pap, and 0.42 to 0.65 for CB. The problem of reproducibility in cervical cytopathology in Mexico emphasizes the need for continuing education, uniform diagnostic criteria, and the advantages of a single operational classification-possibly the Bethesda System-since current classification systems are obsolete.