Abstract
BACKGROUND: Breast density has become a topic of international discussion due to its associated risk of breast cancer. As online is often a primary source of women's health information it is therefore essential that breast density information it is understandable, accurate and reflects the best available evidence. This study aimed to systematically assess online international breast density information including recommendations to women. METHODS: Searches were conducted from five different English-speaking country-specific Google locations. Relevant breast density information was extracted from the identified websites. Readability was assessed using the SHeLL Editor, and understandability and actionability using the Patient Education Materials Assessment Tool (PEMAT). A content analysis of specific recommendations to women was also conducted. RESULTS: Forty-two eligible websites were identified and systematically assessed. The included informational content varied across websites. The average grade reading level across all websites was 12.4 (range 8.9-15.4). The mean understandability was 69.9% and the mean actionability was 40.1%, with 18/42 and 39/42 websites respectively scoring lower than adequate (70%). Thirty-six (85.7%) of the websites had breast density-related recommendation to women, with 'talk to your doctor' (n = 33, 78.6%) the most common. CONCLUSIONS: Online information about breast density varies widely and is not generally presented in a way that women can easily understand and act on, therefore greatly reducing the ability for informed decision-making. International organisations and groups disseminating breast density information need to ensure that women are presented with health literacy-sensitive and balanced information, and be aware of the impact that recommendations may have on practice.