Table 2. Indicators of test performance for detecting advanced neoplasms according to test cut-off.

Indicator of test performance	Cut-off for test positivity (μg Hb/g feces)
	5	9	10	17a	20	25	50
Positivity rate
N	782/1822	287/1822	253/1822	159/1822	138/1822	116/1822	79/1822
%	42.9	15.8	13.9	8.7	7.6	6.4	4.3
95% CI	40.7–45.2	14.2–17.5	12.4–15.5	7.5–10.1	6.4–8.9	5.3–7.6	3.5–5.4
Sensitivity
N	137/207	101/207	93/207	74/207	71/207	66/207	43/207
%	66.2	48.8	44.9	35.7	34.3	31.9	20.8
95% CI	59.5–72.3	42.1–55.6	38.3–51.7	29.5–42.5	28.2–41.0	25.9–38.5	15.8–26.8
Specificity
N	970/1615	1429/1615	1455/1615	1530/1615	1548/1615	1565/1615	1579/1615
%	60.1	88.5	90.1	94.7	95.9	96.9	97.8
95% CI	57.7–62.4	86.8–89.9	88.5–91.5	93.5–95.7	94.8–96.7	95.9–97.6	96.9–98.4
Positive predictive value
N	137/782	101/287	93/253	74/159	71/138	66/116	43/79
%	17.5	35.2	36.8	46.5	51.4	56.9	54.4
95% CI	15.0–20.3	29.9–40.9	31.1–42.9	39.0–54.3	43.2–59.6	47.8–65.5	43.5–65.0
Number needed to scope to detect one advanced neoplasm
N	5.7	2.8	2.7	2.2	1.9	1.8	1.8
95% CI	4.9–6.7	2.4–3.3	2.3–3.2	1.8–2.6	1.7–2.3	1.5–2.1	1.5–2.3

CI, confidence interval; Hb, hemoglobin.

^acut-off recommended by the manufacturer

.