EFFICACY OF THINPREP(R) PREPARATION OF CERVICAL SMEARS - A 1,000-CASE, INVESTIGATOR-SPONSORED STUDY

The diagnoses of 1,000 pairs of conventional Papanicolaou (Pap) smears and ThinPrep(R) preparations were compared. Cervical cells were colle cted using an Ayre spatula and endocervical brush. The conventional sm ear was made first, the collection devices were rinsed into PreservCyt (R) solution, and the slides were prepared using the ThinPrep(R) Proce ssor. The diagnoses of the paired smears agreed in 988 of the 1,000 ca ses (98.8%), including 949 negatives, 28 atypicals, 9 low grade squamo us intraepithelial lesions (LGSIL), and 2 high grade squamous intraepi thelial lesions (HGSIL). Five cases where LGSIL or HGSIL was found on the ThinPrep(R) slide were negative or atypical on the conventional sm ear. No conventional smear abnormalities were missed on the ThinPrep(R ) slide. Although not statistically significant, this difference indic ates that the ThinPrep(R) method gives a better diagnosis of abnormali ties than the conventional method. The ThinPrep(R) method was acceptab le to participating physicians and ThinPreps(R) were easier and faster to screen than conventional smears. (C) 1994 Wiley-Liss, Inc.