Background: Persons with a negative result on screening colonoscopy are recommended to repeat the procedure in 10 years. Objective: To assess the effectiveness and costs of colonoscopy versus other rescreening strategies after an initial negative colonoscopy result. Design: Microsimulation model. Data Sources: Literature and data from the Surveillance, Epidemiology, and End Results program. Target Population: Persons aged 50 years who had no adenomas or cancer detected on screening colonoscopy. Time Horizon: Lifetime. Perspective: Societal. Intervention: No further screening or rescreening starting at age 60 years with colonoscopy every 10 years, annual highly sensitive guaiac fecal occult blood testing (HSFOBT), annual fecal immuno-chemical testing (FIT), or computed tomographic colonography (CTC) every 5 years. Outcome Measures: Lifetime cases of colorectal cancer, life expectancy, and lifetime costs per 1000 persons, assuming either perfect or imperfect adherence. Results of Base-Case Analysis: Rescreening with any method substantially reduced the risk for colorectal cancer compared with no further screening (range, 7.7 to 12.6 lifetime cases per 1000 persons [perfect adherence] and 17.7 to 20.9 lifetime cases per 1000 persons [imperfect adherence] vs. 31.3 lifetime cases per 1000 persons with no further screening). In both adherence scenarios, the differences in life-years across rescreening strategies were small (range, 30 893 to 30 902 life-years per 1000 persons [perfect adherence] vs. 30 865 to 30 869 life-years per 1000 persons [imperfect adherence]). Rescreening with HSFOBT, FIT, or CTC had fewer complications and was less costly than continuing colonoscopy. Results of Sensitivity Analysis: Results were sensitive to test-specific adherence rates. Limitation: Data on adherence to rescreening were limited. Conclusion: Compared with the currently recommended strategy of continuing colonoscopy every 10 years after an initial negative examination, rescreening at age 60 years with annual HSFOBT, annual FIT, or CTC every 5 years provides approximately the same benefit in life-years with fewer complications at a lower cost. Therefore, it is reasonable to use other methods to rescreen persons with negative colonoscopy results.
