Table 2.

Accuracy of sonographic axillary staging for prediction of N0 disease in patients undergoing SNB: whole cohort and patients ≥ 70 years

	Whole cohort	Age ≥ 70 years
	Percentages (95% CI)
Accuracy	94% (93–95%)	95% (93–96%)
Sensitivity	79% (75–82%)	83% (77–88%)
Specificity	100% (99–100%)	100% (99–100%)
Positive predictive value	100% (99–100%)	100% (98–100%)
Negative predictive value	93% (92–94%)	93% (91–95%)
False-negative rate	21% (17–25%)	17% (12–22%)
False-positive rate	0% (0–0.2%)	0% (0–0.7%)