The adequacy of the one-slide cervical smear in the detection of squamous intraepithelial lesions.

This prospective study evaluated the impact of replacing the two-slide cervical smear by a one-slide smear to detect squamous intraepithelial lesions (SIL). The study population consisted of 87 patients with biopsy-proven SILs, a "referral" (precolposcopy) two-slide cervical smear, and a "one-slide repeat" smear done at the time of biopsy. The detection rate of SIL was compared with that of a control group of 85 patients who fulfilled similar criteria; they had a two-slide referral smear, but a "two-slide repeat" smear. Smears nondiagnostic of SIL occurred in 5.7%, 11.8%, 27.6%, and 15.3% in the referral group of the study population, the referral group of the control population, the one-slide repeat smears, and the two-slide repeat smears, respectively. Statistical analysis showed a higher rate of nondiagnostic smears in the one-slide repeat smear (P = .05). Although this may be attributed to the less-than-optimal quality of the preparation, the above findings do not support the use of a one-slide technique for sampling the ectocervix and endocervix.