Table 2.

Diagnostic Yield of “Always Positive” Test^c A Compared with Standard Test S for Colorectal Cancer (CRC), 100,000 Subjects.

Disease	Test Positives			Test Negatives
Status	S+	A+	Δ+	S−	A−	Δ−
Absent	4965	99300	94335	94335	0	−94335
Presenta	525	700	175	175	0	−175
Ratio	9.5	141.9	539.1	539.1	NaN	539.1
FP AEsb	33.8	675.2	641.5
ΔFP AEs/ΔTP			3.67

^aPrevalence of disease (CRC) is assumed to be 0.7%, or 700 per 100,000 subjects.

^bRisk of an adverse event during colonoscopy is assumed to be 0.68% (Rutter et al, 2012, Table 2). All subjects falsely testing positive are assumed to be referred to colonoscopy and undergo the procedure.

^cA trivial test that classifies everyone as test positive for CRC.