Objective: We aimed to evaluate the impact of implementing 100% rapid review (100% RR) as a quality control tool in cervical smear cytology. Design: A cross-sectional study was conducted in which cytology findings, false-negative results, and quality indicators were evaluated. The variables were analyzed in 2004, the year in which 100% RR was implemented, and again in 2013, i.e., 10 years on. Results: Detection of atypical squamous cells of undetermined significance (ASC-US) increased from 0.90% in 2004 to 2.47% in 2013 by routine screening. Detection of atypical squamous cells, cannot exclude a high-grade squamous intraepithelial lesion (ASC-H) increased from 13.33% in 2004 to 36.27% in 2013 by 100% RR. Detection of high-grade squamous intraepithelial lesion (HSIL) increased from 0.64% in 2004 to 4.29% in 2013 by routine screening, and increased from 0% in 2004 to 19.61% in 2013 by 100% RR. There was a significant increase (p = 0.00001) in the identification of false-negative results of ASC-US, low-grade squamous intraepithelial lesion, ASC-H, HSIL, and atypical glandular cells. All quality indicators had increased in 2013 when compared to 2004 results. Conclusions: Ten years after the implementation of the 100% RR method, improvements were found in the detection of atypia and precursor lesions and in quality indicators.

RPS is an effective alternative method of internal quality control with high sensitivity for the detection of more severe lesions. It also permits monitoring of the laboratory rate of false-negative results, and allows constant evaluation of the performance both of the pre-screening and RS cytologists.