Interobserver variability in subclassification of squamous intraepithelial lesions: Results of the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology.
OBJECTIVE
To determine whether, on a national cytology proficiency test, a competent cytologist can consistently distinguish grades of squamous intraepithelial lesions.


METHODS
Results for low- and high-grade squamous intraepithelial lesion referenced slides from the College of American Pathologists Interlaboratory Comparison Program in Cervicovaginal Cytology for 1996 and 1997 were analyzed including educational, nongraded vs graded validated slides.


RESULTS
The discrepant rate between low- and high- grade lesions ranged from 9.8% to 15% for cytotechnologist, pathologist, laboratory, and all responses. There was a statistically significant difference in performance on graded, validated slides vs educational slides with better performance on validated slides.


CONCLUSIONS
This significant interobserver variability in subclassification of squamous lesions should be considered in management guidelines for abnormal Papanicolaou test results and implementation of national cytology proficiency testing.
Woodhouse
S L
SL
Division of Pathology and Laboratory Medicine, Cleveland Clinic Hospital, Florida, Ft Lauderdale 33308, USA.
Stastny
J F
JF
Styer
P E
PE
Kennedy
M
M
Praestgaard
A H
AH
Davey
D D
DD
D002294:Carcinoma, Squamous Cell / Q000145:classification* / Q000175:diagnosis; D005260:Female; D006801:Humans; D015588:Observer Variation; D065006:Papanicolaou Test; D012015:Reference Standards; D012955:Societies, Medical; D014481:United States; D002583:Uterine Cervical Neoplasms / Q000145:classification* / Q000175:diagnosis; D014626:Vaginal Smears / Q000145:classification* / Q000592:standards / Q000706:statistics & numerical data; D002578:Uterine Cervical Dysplasia / Q000145:classification* / Q000175:diagnosis