Utility valuations for outcome states of colorectal cancer

OBJECTIVE: Utilities for the outcome states of colorectal cancer (CRC) must be measured to evaluate the cost-utility of screening and surveillance str ategies for this disease. We sought to measure utilities for stage-dependen t outcome states of CRC. METHODS: We identified persons who had previously undergone removal of colo rectal adenoma. We conducted individual interviews in which these participa nts were presented with stage-dependent outcome states and were asked to as sess utilities for them using the standard gamble technique. RESULTS: A total of 90 participants were interviewed; nine were excluded, l eaving 81 for analysis. We obtained the following utility valuations: stage I rectal or stage I/II colon cancer (mean 0.74, median 0.75); stage III co lon cancer (mean 0.67, median 0.75); stage II/III octal cancer without osto my (mean 0.59, median 0.60), stage II/III rectal cancer with ostomy (mean 0 .50, median 0.55), stage IV rectal or colon cancer (mean 0.25, median 0.20) . These valuations were statistically different from each other. CONCLUSIONS: We measured utilities for stage-dependent outcome states of CR C in a sample of persons who had previously undergone removal of colorectal adenoma. We found that our participants were able to differentiate between the presented outcome states and assigned lower utility to increasingly mo rbid states. Our results show that stage-dependent morbidity is an importan t consideration in CRC and should be incorporated into any decision analysi s model evaluating the cost-effectiveness of CRC screening or surveillance. (Am J Gastroenterol 1999;94:1650-1657. (C) 1999 by Am, Cell. of Gastroente rology).