Community health service center is the main gatekeeper for breast cancer screening, while its efficacy of screening is difficult to guarantee for the re-striction of screening process by various factors.

To analyze the focus issue of breast cancer screening program in the real world and explore corresponding solutions.

A mixed-methods convergent design was used to collect quantitative and quali-tative data. In the quantitative study, typical sampling method was used to select one community health service center in each of the four districts of Tianjin as the investigation institution from April 2021 to November 2022, accidental sampling method was used to select age-eligible women within 3 km of the four institutions as resident survey respondents, so as to explore the issues existing in the on-site operation of breast cancer screening. In the qualitative study, 9 residents, 12 physicians participating in the screening and 4 leaders were selected through purposive sampling from June to November 2022 for semi-structured in-terviews. The grounded theory was used to analyze the interview content, and the grounded theory framework of the focus issues of breast cancer screening was plotted. Combined with literature and typical investigation data, a mixed methods study was conducted to determine the focus issues of breast cancer screening.

The quantitative study showed that in the advocacy work, the promotion method is traditional, the awareness rate and participation rate of residents was 46.3% (143/309) and 32.4% (100/309) , respectively; in the screening work, the institutions invested different human and material resources, and the average waiting time of screening residents accounted for 62.2% (40.5/65.1) of the total time; in the follow-up and referral work, the invested human and material resources were little, the mammography referral compliance of residents was 29.9% (59/197) . The qualitative study showed that a total of 38 comprehensive open codes were formed in the interview and converged into 10 axial codes and 3 core codes, including advocacy organization, screening organization, follow-up and referral. The mixed methods study showed that 3 focus issues were identified in final, including how to improve residents' participation rate, how to ensure adequate human and material resources in screening institutions, and how to improve residents' mammography referral compliance.

The efficacy of breast cancer screening is influenced by advocacy organization, screening organization, follow-up and referral. It is necessary to rationally allocate resources to ensure adequate human and material resources for screening institutions; innovate promotion methods, expand coverage of promotion and improve residents' health literacy, participation rates and mammography referral compliance, to ensure the substantial progress of breast cancer screening and provide reference for opti-mizing the efficacy of breast cancer screening.