Personalised informed choice on evidence and controversy on mammography screening: study protocol for a randomized controlled trial.

Background: In Italy women aged 50-69 are invited for a population-based breast cancer (BC) screening. Physicians, policy makers and patients 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.

Methods/design: The impact of the DA will be evaluated in a randomized controlled trial with a two-week follow-up. Women will be randomized via web to DA or a standard brochure. We will invite 8160 women, to obtain a final sample of 816 women. The primary outcome will be informed choice, measured on the basis of knowledge, attitudes and intentions on BC screening. Secondary outcomes are participation rate, satisfaction on information and decisional conflict.

Discussion: The web DA will be open-source and implemented on BC screenings and its efficacy for increasing informed choice will be tested. This model could be applied to other healthcare settings, cancer screenings, and public health programs.

Trial Registration: The protocol for this trial was registered with the Clinicaltrials.gov registry on March 16, 2017: NCT03097653 .