Evaluation of the 10% rescreen of negative gynecologic smears as a quality assurance measure.

The CLIA '88 regulations require the laboratory to review at least 10% of the gynecologic cases interpreted as negative that are examined by each cytotechnologist. The review must include negative cases selected at random and from patients identified as a high risk group. To evaluate the validity of this regulation, we reviewed the results of the 10% rescreen over a 24-mo period. The rescreening by pathologists detected epithelial abnormalities in 4/2,124 negative cases (0.18%). Subsequently, biopsy-proven squamous intraepithelial lesions were found in all four cases. Three different cytotechnologists were responsible for the four false-negative interpretations. Our results show that 10% rescreen of negative smears may detect a few false-negative cases. However, it is a time-consuming and inefficient mean to evaluate the performance of cytotechnologists. Quality control in gynecologic cytopathology is essential, but it is equally important that laboratories concentrate their resources and energy on methods proven to be effective.