Interobserver variability of cervical smears with squamous‐cell abnormalities: A philadelphia study

TLDR

The study assessed TBS reproducibility by having five cytopathology experts classify 20 Pap smear slides, including four classic cases and 16 selected for potential diagnostic discrepancies. Unanimous agreement occurred in 35% of cases, while 35% differed by one category and 30% by more than one; although additional comments often mitigated clinical impact, the study highlights substantial subjectivity in TBS classification of non‑classic squamous abnormalities. Published in Diagn Cytopathol 1994;11:352–357; © 1994 Wiley‑Liss, Inc.

Abstract

Abstract The reproducibility of reporting squamous lesions by the Bethesda System (TBS) was evaluated by distributing 20 slides to be classified among 5 panelists considered experts in the field of cytopathology. Four cases were chosen for their classic morphology and the remainder were foreseen to produce possible discrepancies within one diagnostic category. For 7/20 (35%) cases there was unanimous agreement. Participants disagreed within one category of magnitude for seven (35%) cases. In six (30%) cases there was a range of more than one category disagreement. However, additional written comments modifying TBS diagnoses often diminished the clinical significance of these discrepancies. We conclude that despite the important role of TBS in standardization of Pap smear reports, a great degree of subjectivity exists in classifying squamous abnormalities without “classic” morphology. The lack of reproducibility should be taken into account in cytology proficiency testing. Diagn Cytopathol 1994;11:352–357. © 1994 Wiley‐Liss, Inc.