Table 3. Comparison of emergency department clinician–predicted gFOBT results with the actual results.

gFOBT: guaiac fecal occult blood test

^aP value determined by Wilcoxon rank sum test

Predicted likelihood of positivity	Positive result (n=78), n (%)	Negative result (n=54), n (%)	Pa
No chance	0 (0.0)	2 (3.7)	< .001
Slight possibility	7 (9.0)	24 (44.4)
Fair possibility	16 (20.5)	13 (24.1)
Very probable	32 (41.0)	9 (16.7)
Certain	23 (29.5)	6 (11.1)