Accuracy of Colposcopically Directed Biopsy: Results from an Online Quality Assurance Programme for Colposcopy in a Population-Based Cervical Screening Setting in Italy

Table 2

Nonbiopsy and incorrect selection of biopsy site according to original histological diagnosis.

	CIN1^a	CIN2	CIN3/AIS	Carcinoma	Total
Colposcopist decision on biopsy
No	48	5	9	2	64
Yes, incorrect site	35	21	75	2	133
Yes, correct site	330	210	860	232	1632
Yes, subtotal	365	231	935	234	1765
Total	413	236	944	236	1829
Nonbiopsy rate	0.12 (0.09–0.15)	0.02 (0.01–0.05)	0.01 (0.00–0.02)	0.01 (0.00–0.03)	0.03 (0.03-0.04)
Incorrect biopsy site rate	0.08 (0.06–0.12)	0.09 (0.06–0.13)	0.08 (0.06–0.10)	0.01 (0.00–0.03)	0.07 (0.06–0.09)
Total biopsy failure rate	0.20 (0.16–0.24)	0.11 (0.07–0.15)	0.09 (0.07–0.11)	0.02 (0.00–0.04)	0.11 (0.09–0.12)

CIN: cervical intraepithelial neoplasia; AIS: adenocarcinoma in situ.
^aFifty-nine CIN1 cases were excluded from evaluation because the committee did not consider them worthy of biopsy based on colposcopic findings and, thus, did not classify the correctness of biopsy site as indicated (if any) by the colposcopists.