Does a decision aid improve informed choice in mammography screening? Study protocol for a randomized controlled trial

Abstract

BackgroundWhen invited for the first time at age 50, most women in Germany have to decide whether they wish to participate in the German mammography screening programme. For ethical reasons, screening decisions should be informed choices, but this is rarely the case with mammography screening. Decision aids are interventions with the potential to support informed choice by improving the following factors: knowledge, clarity of personal attitude, and implementation of an intention. Currently, no systematically evaluated decision aid exists for the German mammography screening programme. Therefore, the objective of this randomized controlled trial is to assess the effectiveness of a decision aid for first-time mammography screening programme invitees.Methods/DesignWe have developed a decision aid for women invited to the mammography screening programme for the first time based on the criteria of the International Patient Decision Aids Standards Collaboration. The effectiveness of the decision aid will be evaluated in a randomized controlled trial with a 3-month follow-up. We will invite 7400 women aged 50 years from the district of Westfalen-Lippe, Germany, to participate. This sample will be drawn from registration office data. The primary outcome will be informed choice. The secondary outcomes will be the components of informed choice (knowledge, attitude, decision/implementation). Decisional conflict, decision regret, eHealth literacy, health behaviours, perceived behavioural control, subjective norms, invitation status, and demographic variables will be assessed. Data will be collected online at baseline, post-intervention, and at the 3-month follow-up. Participants will be randomized to receive either the decision aid or usual care (invitation and standard leaflet of the mammography screening programme).DiscussionThis paper describes the evaluation of a decision aid for the German mammography screening programme in a randomized controlled trial. If the decision aid proves to be an effective tool to enhance the rate of informed choice, it will be made accessible to the public and the use of this decision aid for first-time invitees will be recommended. The long-term effect could be an improvement in informed choices in women invited to the mammography screening programme.Trial registrationGerman Clinical Trials Register DRKS00005176.Electronic supplementary materialThe online version of this article (doi:10.1186/s12905-015-0210-5) contains supplementary material, which is available to authorized users.

Client and practitioner perspectives on the screening mammography experience

“…In addition, if practitioners perceive that their clients are not necessarily making an informed choice to be screened, this can be professionally problematical and therefore stressful. Knowledge and attitudes, and whether behaviour is in line with these, are widely described as components of informed decision‐making (Hersch et al., ; Jepson, Hewison, Thompson, & Weller, ; Mullen et al., ; Reder & Kolip, ). Levels of knowledge about the potential harms of screening were mostly low among our participants but, unsurprisingly for a sample of attenders, they did not express dissatisfaction with their knowledge about screening.…”

Does a decision aid improve informed choice in mammography screening? Results from a randomised controlled trial

“…The invitation to the study was sent by post 3 weeks before the estimated arrival of the MSP invitation (for more details, see the study protocol [ 6 ]). Three weeks after the postal invitation, women consenting to study participation and providing their e-mail address received the link to the baseline questionnaire (T1).…”

“…Our Online DA consisted of a static information part and an interactive part (see study protocol for a more detailed description [ 6 ]). Mathieu et al’s DA [ 13 ] provided the basis for developing the structure of our DA.…”

“…In the information part, the chance of each outcome was expressed as event rate per 200 women screened every 2 years for 20 years using absolute numbers accompanied by crowd figure pictograms (see additional file of the protocol [ 6 ]). The advantages and disadvantages of the MSP and their probabilities were described.…”

“…A decision is classified as informed, if the decision maker has good knowledge about the options, her/his attitude is congruent with the decision, and she/he then implements this decision [ 5 ]. To enable women invited to the MSP to such an informed choice, they need to be informed about the existing benefits and harms including their probability and to be supported in clarifying the meanings of those benefits and harms for themselves [ 6 ]. Importantly, no correct course of action can be determined [ 7 ]—only a personally preferred course of action.…”