[Decision aid and informed decision on breast cancer screening: the "DonnaInformata-Mammografia" project.]

In Italy women aged 50-69 are invited for a population-based breast cancer (BC) screening. Physicians, policy makers and patient associations agree on the need to inform women about the benefits and harms in order to permit an informed decision. Decision aids (DA) are an effective way to support people in their decisions about health. This trial aims to assess women's informed choices, according to their health literacy and values, on participating or not in BC screening for the first time. Benefits, harms and controversies are presented. The contents of the DA were developed on the basis of: a) findings of three focus groups and four interviews, organized in the three Italian screening centers; b) analysis of the literature. A web-based platform (www.donnainformata-mammografia) was developed to implement the DA in a multilevel model. The impact of the DA will be evaluated in a randomized controlled trial with a one week follow-up. The women will be randomized to DA or a standard brochure via web. We will invite 8160 women to obtain the final sample size of 816 women. The primary outcome will be informed choice, measured via knowledge, attitudes and intentions on BC screening.

participation rate and decisional conflict process. If the informed choice will be reached, the web DA will be open source and could be implemented in BC screenings. This model could be applied to other health care settings and cancer screenings.