Intralaboratory quality assurance in cervical/vaginal cytology: evaluation of intercytologist diagnostic reproducibility.

Diagnostic reproducibility and accuracy in evaluating cervical/vaginal smears were the focus of this study concerning intralaboratory quality control. A set of 120 cytological samples was evaluated by 15 cytopathologists whose experience ranged from 3-29 yr. The study report form was based on the 1988 Bethesda System. Intercytologist reproducibility (with respect to sample adequacy, epithelial cell abnormalities, and presence of cellular changes associated with HPV, Human Papilloma virus) was evaluated using the Kappa statistic. Poor reproducibility in defining sample adequacy was observed (K = 0.24). The agreement on epithelial cell abnormality definition was good (K = 0.64); the lowest reproducibility was observed for High-grade squamous intraepithelial lesion/cervical intraepithelial neoplasia HSIL/CIN II (specific K = 0.37) and Atypical cells of undetermined significance ACUS (specific K = 0.44). The agreement in detecting cellular changes associated with HPV was fair (K = 0.49). Diagnostic accuracy for epithelial cell abnormalities, assessed by comparison with a consensus reference diagnosis, was good (K = 0.74).