Value-of-Information Analysis to Guide Future Research in Colorectal Cancer Screening

Purpose: To identify the most useful areas for research in colorectal cancer (CRC) screening by using a value-of-information analysis. Materials and Methods: Cost-effectiveness of screening strategies, including colonoscopy, computed tomographic (CT) colonography, flexible sigmoidoscopy, and barium enema examination, were compared by using a Markov model. Monetary net benefit (NB), a measure of cost-effectiveness, was calculated by multiplying effect (life-years gained) by willingness to pay ($100 000 per life-year gained) and subtracting cost. A value-of-information analysis was used to estimate the expected benefit of future research that would eliminate the decision uncertainty. Results: In the reference-case analysis, colonoscopy was the optimal test with the highest NB ($1945 per subject invited for screening compared with $1862, $1717, and $1653 for CT colonography, flexible sigmoidoscopy, and barium enema examination, respectively). Results of probabilistic sensitivity analysis indicated that colonoscopy was the optimal choice in only 45% of the simulated scenarios, whereas CT colonography, flexible sigmoidoscopy, and barium enema examination were the optimal strategies in 23%, 16%, and 15% of the scenarios, respectively. Only two parameters were responsible for most of this uncertainty about the optimal test for CRC screening: the increase in adherence with less invasive tests and CRC natural history. The expected societal monetary benefit of further research in these areas was estimated to be more than $15 billion. Conclusion: Results of value-of-information analysis show that future research on the optimal test for CRC screening has a large societal impact. Priority should be given to research on the increase in adherence with screening by using less invasive tests and to better understanding of the natural history of CRC. (C) RSNA, 2009