Reproducibility of cervical cytopathology following an intervention by an external quality control laboratory.

Abstract

This study assessed the effects of a continued education program on the agreement between cervical cytopathology exams interpreted by local laboratories and interpretation made by an external quality control laboratory (LabMEQ). Overall, 9,798 exams were analyzed between 2007 and 2008, prior to implementation of a continued education program, and 10,028 between 2010 and 2011, following implementation. Continued education consisted of theoretical and practical classes held every two months. The chi-square test and the kappa coefficient were used in the statistical analysis. Following implementation of continued education, the rate of false-negative results, and those leading to delays in clinical management fell in eight laboratories and the rate of false-positive results in five. Agreement between the results reported by the laboratories and the findings of LabMEQ, evaluated according to clinical management, remained excellent in three laboratories (kappa >0.80 and <1.0), went from good (kappa >0.60 and <0.80) to excellent in seven and from excellent to good in two. Agreement regarding the identification of metaplastic epithelium was poor (kappa = 0.25) but progressed to excellent following the implementation of continued education (kappa = 0.950). Agreement between cytopathology results improved significantly following implementation of continued education in cases reported as unsatisfactory (P < 0.001), atypical squamous cells of undetermined significance, cannot exclude high-grade squamous intraepithelial lesion (P < 0.001), low-grade squamous intraepithelial lesion (P < 0.001), and glandular atypia (P < 0.001). Continued education contributed towards improving the reproducibility of cervical cytopathology, decreased the rates of false-negative and false-positive results, and reduced delays in clinical management.