The atypical squamous cell/squamous intraepithelial lesion (ASC/SIL) ratio has been used as a surrogate quality control tool for specificity and uncertainty for cytopathologists. Whether this ratio is useful for cytotechnologists is not known. During an 8-month period, the sensitivity of screening for 11 cytotechnologists was determined using rapid prescreening. The ASC/SIL ratio for each cytotechnologist was correlated with the screening accuracy for each. Screening sensitivity varied from 50.5% to 97.7%, and the ASC/SIL ratio varied from 0.87 to 4.49. The mean screening sensitivity for cytotechnologists with ASC/SIL ratios less than 1.5 was significantly less than that of cytotechnologists whose ASC/SIL ratio was more than 3.0 (67% vs 95%; P = .021). In the absence of more accurate quality control data, an ASC/SIL ratio less than 1.5 for a cytotechnologist may be a surrogate marker for inadequate screening sensitivity.