Misinterpretation Rates of High-Grade Squamous Intraepithelial Lesion in the College of American Pathologists Gynecologic PAP Education and PAP Proficiency Test Program.

Context.— Misinterpretation of high-grade squamous intraepithelial lesion (HSIL) is an important problem in daily practice and in the College of American Pathologists (CAP) PAP Proficiency Test (PAP-PT). Objective.— To investigate factors related to misinterpretation of HSIL through responses in a proficiency test versus an educational environment. Design.— We retrospectively evaluated 28 000 responses in the PAP Education Program (PAP-Edu) and 59 140 responses in PAP-PT from 1147 field-validated HSIL slides from 2007 to 2014. The related factors, such as program types, preparation types, participant types, and program years, were evaluated. Results.— Overall, 4.0% (2379 of 59 140) of responses for HSIL slides from PAP-PT were misinterpreted as either low-grade squamous intraepithelial lesion (LSIL) or negative, significantly more than those from PAP-Edu (3.2%; 898 of 28 000). However, the false-negative rate (misinterpreted as negative) was 0.9% (519 of 59 140) for PAP-PT, lower than that for PAP-Edu (1....