Table 4.

Test characteristics of visual inspection with acetic acid as primary screening test and cytology as a triage test, using positive histology or negative colposcopy as the gold standard

Parameter	Cytology as triage
	Disease status ≥ CIN 1				Disease status ≥ CIN 2
	≥ ASCUS		≥ LSIL		≥ ASCUS		≥ LSIL
	Percentage	95% CI	Percentage	95% CI	Percentage	95% CI	Percentage	95% CI
Sensitivity	25.9	15.3-39	13.8	6.15-25.4	75.0	42.8-94.5	50.0	21.1-78.9
Specificity	95.3	93.2-97	98.8	97.5-99.6	94.7	92.5-96.4	98.6	97.2-99.4
PPV	38.5	23.4-55.4	57.1	28.9-82.3	23.1	11.1-39.3	42.9	17.7-71.1
NPV	92.0	89.3-94.1	91.1	88.4-93.3	99.4	98.4-99.9	98.9	97.7-99.6
FPR	4.65		1.16		5.34		1.42
FNR	74.14		86.21		25.0		50.0

ASCUS: Atypical cells of undetermined significance, CIN: Cervical intraepithelial neoplasia, LSIL: Low-grade squamous intraepithelial lesions, NPV: Negative predictive value, PPV: Positive predictive value, FPR: False-positive rates, FNR: False-negative rates, CI: Confidence interval