OBJECTIVES: Fifty-one percent of people do not participate in non-invasive colorectal cancer screening. One of the reasons may be the prospect of a future invasive follow-up test (colonoscopy). We investigate how follow-up test information affects peoples’ participation decision and screening test preferences and expect a negative effect on participation when colonoscopy is specified as follow-up test. METHODS: Attributes and levels in the DCE are based on a literature review and analysis of CRC related mortality-risk (data Erasmus MC). We created a labeled and blocked efficient design with zero priors and restrictions in Ngene. The labels represent three different screening tests (a stool-test, blood-test, combi-test) and a non-participation option. Two follow-up test specification versions and 3 blocks resulted in six different web-based survey versions of 12 choice sets each. The colonoscopy specification version presents respondents an additional follow-up test attribute with colonoscopy as a fixed attribute level and detailed colonoscopy information. The non-colonoscopy specification version doesn’t present respondents a follow-up test and follow-up test information. Respondents were randomly assigned to one of the survey versions. Data of 631 Dutch respondents, aged 55-75 years, is used in the analysis. RESULTS: MNL model results show a positive significant effect on screening test choice for the attributes sensitivity, risk reduction, and level of evidence, and a negative effect of 1-specificity. The significant negative interaction effects of the alternative specific constants with follow-up test specification indicate that uptake would be lower in case a colonoscopy is specified (83.8% versus 88.6%). Furthermore, the difference between the (more preferred) combi-test relative to the other tests diminishes for the colonoscopy specification. A nested logit model doesn’t indicate scale differences. CONCLUSIONS: People’s screening test preferences are affected by invasive follow-up test (colonoscopy) information presented in the survey. This result is interesting for policy makers that aim to optimize uptake.