The goal of this clinical trial is to learn if a behavioral "nudge" strategy, specifically a default option, can improve screening participation in populations at high risk for lung and stomach cancer. The main questions it aims to answer are:
1. Does presenting a screening appointment as a default option increase the likelihood that high-risk individuals will choose to be screened?
2. How do participants react, and what is their level of acceptance, when the nudge intervention is disclosed to them?
3. Does this transparency (disclosing the nudge) change their subsequent screening decisions? Researchers will compare a default option group to a standard control group to see if the nudge effectively increases screening adherence.
Participants will:
1. Read a short educational text about lung or stomach cancer and its screening.
2. Complete an online questionnaire.
3. Make a decision regarding a simulated cancer screening appointment.
4. Read a disclosure explaining the behavioral nudge strategy used during the study.
5. Re-evaluate their screening decision and answer questions regarding their attitude toward the nudge.