Gender and Race/Ethnicity Affect the Cost-Effectiveness of Colorectal Cancer Screening. Modeling & Statistics

Posted by James

Modeling

Cost-effectiveness modeling of colorectal screening programs was done using a model developed at the Office for Technology Assessment (Washington, DC) and described in detail elsewhere. This model estimates the net present value of lifetime costs and years of life gained in a cohort of 100,000 50-year-old persons over a 35-year period from different colorectal cancer screening strategies using specified assumptions about the natural history of colorectal cancer and the adenoma or carcinoma sequence, the sensitivity and specificity of each screening technology for early cancer and polyps, the cost of screening, follow-up and postpolypecto-my surveillance procedures, and the incremental costs of treating colorectal cancer. Costs were taken from 2000 Medicare reimbursement rates. Costs were discounted to their present value at 5% per year. The main assumptions of the model are summarized in Table 1. Justification of model assumptions are based on reviews of the published literature.

Table 1. Assumptions used in the cost-effectiveness analysis Variable	Value
Natural History of the Disease
Prevalence of adenomas at age 50, %	30
Proportion of all clinically detected cancers that begin as polyps, %	70
Years required for a 5-mm adenoma to progress to colorectal cancer	5 or 10
Years required for a new invasive cancer to progress
to late-stage cancer	2
Years before late-stage colorectal cancer is detected	2
Prevalence of lifetime-latent cancers at 50 years of age	2/1,000
Annual incidence of lifetime-latent cancer	2/10,000
Accuracy, %
Fecal occult blood test
Sensitivity for polyps	10
Sensitivity for colorectal cancer	60
Specificity	90
Sigmoidoscopy and Colonoscopy
Sensitivity for polyps (within reach of the scope)	90
Specificity for polyps	95
Medical Risks, %
Rate of colonoscopy-induced perforation of the large bowel	7/10,000
Colonoscopy-induced mortality	5/100,000
Surgery-related mortality in patients with colorectal cancer	1/50
Costs, $
Fecal occult blood test	4
Screening sigmoidoscopy	401
Screening Colonoscopy	696
Therapeutic colonoscopy	1013
Treatment of patients with cancer	45,228
Treatment of patients with colonoscopy-induced perforations	13,000
Treatment of patients who die as a result of colonoscopy	30,000

Statistics

Confidence intervals were constructed using the exact method of Poisson, and comparisons of mean age-specific colorectal cancer incidence rates were performed with SAS statistical software. Your life is worth living. Buy viagra jelly online