This study will evaluate whether a precision navigation intervention can help community residents at high risk for cancer complete recommended cancer screening. The study will be conducted in communities participating in an urban cancer screening program in China.

Eligible participants will be adults aged 45 to 74 years who are permanent residents of participating communities and have been identified as being at high risk for at least one of five cancers: lung cancer, breast cancer, colorectal cancer, upper gastrointestinal cancer, or liver cancer. Participants must not have completed the corresponding free clinical screening before enrollment.

This is a dual-cohort, cluster randomized controlled trial. Communities, rather than individual participants, will be assigned to one of three groups: a precision navigation group, a usual health education group, or a waiting control group. Participants will be classified into two cohorts according to the number of cancers for which they are assessed as high risk. Cohort A will include participants at high risk for three or more cancers, and Cohort B will include participants at high risk for one or two cancers.

Participants in the precision navigation group will receive a personalized navigation report matched to their risk profile. The report will explain the screening tests most relevant to them, help them understand screening choices, and provide practical steps to support screening completion. Participants in the usual health education group will receive general cancer screening education materials. Participants in the waiting control group will not receive active screening promotion during the main intervention period, but will receive general education materials after the primary assessment.

The main outcome is whether participants complete the recommended cancer screening during follow-up. The study will also assess changes in screening-related decision conflict, anxiety, self-efficacy, and behavioral intention.

The results may help improve community-based cancer screening programs and provide evidence for using personalized navigation strategies to increase screening participation among high-risk populations.

Inclusion Criteria:

1. Aged 45 to 74 years.
2. Permanent resident of a participating community, defined as having lived in the community for at least 6 months during the past 12 months.
3. Participating in the urban cancer screening program.
4. Identified by the program risk assessment questionnaire as being at high risk for at least one of the following cancers: lung cancer, breast cancer, colorectal cancer, upper gastrointestinal cancer, or liver cancer.
5. Has not yet completed the corresponding free clinical screening test for the high-risk cancer type or types.
6. Able to complete electronic questionnaires and read intervention materials independently or with assistance. Paper materials and staff explanation will be provided for participants who do not use smartphones.
7. Able and willing to provide written informed consent.

Exclusion Criteria:

1. Previously diagnosed with any of the target cancers, including lung cancer, breast cancer, colorectal cancer, upper gastrointestinal cancer, or liver cancer.
2. Severe cognitive impairment, severe mental illness, or other conditions that prevent the participant from receiving the intervention or completing study questionnaires.
3. Planning to be away from the community for a long period during the next 6 months, defined as cumulative absence of more than 3 months.
4. Currently participating in another interventional study that may affect cancer screening behavior.