The sensitivity, specificity, predictive values, and likelihood ratios of fecal occult blood test for the detection of colorectal cancer in hospital settings

Figures & data

Table 1 Performance characteristics of FIT compared with G-FOBT among the screening and control groups

G-FOBT	FIT				Total
	Screening group		Control group
	Positive	Negative	Positive	Negative
Positive	26	32	13	0	71
Negative	5	194	3	4	206
Total	31	226	16	4	277

Note: Chi-squared =108.93; P<0.0001.

Abbreviations: FIT, fecal immunochemical test; G-FOBT, guaiac fecal occult blood test.

Table 2 Performance characteristics of G-FOBT for detecting colorectal cancer

G-FOBT	Screening group		Total	Control group
	Colorectal cancer			Colorectal cancer
	Positive	Negative
Positive	2	56	58	13
Negative	2	197	199	7
Total	4	253	257	20

Note: Chi-squared =1.75; P=0.19.

Abbreviation: G-FOBT, guaiac fecal occult blood test.

Table 3 Performance characteristics of FIT for detecting colorectal cancer

FIT	Screening group		Total	Control group
	Colorectal cancer			Colorectal cancer
	Positive	Negative
Positive	3	25	28	16
Negative	1	228	229	4
Total	4	253	257	20

Note: Chi-squared =17.20; P=0.00.

Abbreviation: FIT, fecal immunochemical test.

Table 4 Sensitivity, specificity, and predictive values and 95% CI (between parenthesis) of G-FOBT and FIT for colorectal cancer (n=277)

	G-FOBT	FIT
Sensitivity	50.00% (6.76–93.24)	75.00% (19.41–99.37)
Specificity	77.87% (72.24–82.83)	90.12% (85.76–93.50)
Positive likelihood ratio	2.26 (0.83–6.18)	7.59 (3.86–14.94)
Negative likelihood ratio	0.64 (0.24–1.71)	0.28 (0.05–1.52)
Positive predictive value	3.45% (0.42–11.91)	10.71% (2.27–28.23)
Negative predictive value	98.99% (96.42–99.88)	99.56% (97.59–99.99)

Abbreviations: CI, confidence interval; G-FOBT, guaiac fecal occult blood test; FIT, fecal immunochemical test; n, number.

Table 5 The sensitivities and 95% CI (between parentheses) of a single G-FOBT and FIT by different anatomic stages of colorectal cancer

	n	G-FOBT positive cases	G-FOBT sensitivity % (95% CI)	FIT positive cases	FIT sensitivity % (95% CI)
Stage I	2	1	50.0 (1.26–98.74)	1	50.0 (1.26–98.74)
Stage II	15	8	53.33 (26.59–78.73)	9	60.0 (32.29–83.66)
Stage III	3	2	66.67 (9.43–99.16)	2	66.67 (9.43–99.16)
Stage IV	3	2	66.67 (9.43–99.16)	3	100.00 (29.24–100.00)
P-value		t=3.68; P=0.066		t=2.83; P=0.005

Abbreviations: CI, confidence interval; G-FOBT, guaiac fecal occult blood test; FIT, fecal immunochemical test; n, number.