Worldwide review with meta-analysis of women's awareness about breast cancer.

Objective: To summarize the awareness levels of breast cancer (BC) worldwide and investigate factors associated with BC awareness to determine differences in awareness between China and other countries.

Methods: This systematic review followed the PRISMA guidelines and included 92 articles up to July, 2021. We calculated percentages for BC awareness levels and conducted subgroup analysis and cumulative meta-analysis.

Results: A total 84% (95% confidence interval [95%CI]: 78-90%) of women knew about BC; however, only 51% (95%CI: 37-66%) and 40% (95%CI: 24-56%) of women were aware of BC symptoms and BC risk factors, respectively. The most commonly known BC symptom was breast lump (71%, 95%CI: 62-80%), and BC family history was the most well-known BC risk factor (61%, 95%CI: 54-69%). Subgroup analysis showed lower awareness levels among Chinese and Asian women than women from other countries. Cumulative meta-analysis showed no obvious progress in BC awareness levels over time. We investigated 15 awareness-related factors, the most frequent of which were education level (61.8%), occupation (29.4%), and age (26.5%).

Conclusion: BC awareness levels remain low. Improving BC awareness is critical, especially in developing countries.

Practice Implications: Effective education programs are urgently needed to improve women's BC awareness.