Table 1.

Model Assumptions

	Base Case	Sensitivity Analysis Range	References
Natural History
Prevalence of adenomatous polyps			15–19
Age 50 yr	20%	10–30%
Age 60 yr	40%	30–50%
Age 70 yr	50%	40–60%
Age 80 yr	55%	45–65%
In patients with adenomas:
Proportion of adenomas that are high-risk	15%	5–25%	15–19
Annual incidence of colorectal cancer			2
Age 50 yr	0.05%	–
Age 55 yr	0.09%	–
Age 60 yr	0.14%	–
Age 65 yr	0.20%	–
Age 70 yr	0.27%	–
Age 75 yr	0.35%	–
Age 80 yr	0.43%	–
Age 85 yr	0.45%	–
5-yr colorectal cancer mortality			20
Localized	10.5%	–
Regional	35.1%	–
Disseminated	91.7%	–
Test Characteristics
Sensitivity of 2-D VC for adenomas 1–5 mm	33%	14–57%	13
Sensitivity of 2-D VC for adenomas 6–9 mm	50%	30–83%	13
Sensitivity of 2-D VC for adenomas ≥ 10 mm	82%	55–95%	13
Specificity of 2-D VC	91%	85–97%	13
Sensitivity of 3-D VC for adenomas 1–5 mm	46%	25–56%	13
Sensitivity of 3-D VC for adenomas 6–9 mm	83%	42–94%	13
Sensitivity of 3-D VC for adenomas ≥10 mm	91%	80–100%	13
Specificity of 3-D VC	91%	85–97%	13
Sensitivity of FOBT for adenomas	5%	2–10%	21–27
Specificity of FOBT	97.5%	90–100%	21–23;26;27
Sensitivity of FOBT for cancer			21;23–27
Localized	30%	20–40%
Regional	50%	40–60%
Neoplasia reachable by sigmoidoscopy	55%	40–75%	5;28–30
Sensitivity of optical colonoscopy/sigmoidoscopy for adenomas < 1 cm	85%	80–95%	29;31–36
Sensitivity of optical colonoscopy/sigmoidoscopy for adenomas > 1 cm or cancer	95%	90–100%	29;31–36
Perforation rate—optical colonoscopy	0.1%	0.0–0.3%	37–39
Mortality rate—perforation	7.5%	5–10%	28;40
Costs
CT colonography	$559	$100–$1,400	41
Fecal occult-blood testing	$18	$5–$30	42
Flexible sigmoidoscopy	$389	$100–$500	41
Flexible sigmoidoscopy with biopsy and pathology	$492	$100–$550	41
Optical colonoscopy	$653	$150–$1,400	41;43
Polypectomy (including pathology)	$178	$100–$300	41
Cancer care			28;44–52
Localized	$34,300	$20,000–$60,000
Regional	$47,230	$30,000–$80,000
Disseminated	$41,600	$30,000–$70,000
Cost of treating colon perforation	$22,269	$10,000–$30,000	40;47