iDecide: the Advance Directive app to facilitate engagement in Advance Care Planning

Advance Directives (AD) are central to Advance Care Planning (ACP), allowing patients to document medical preferences in legally binding documents. Despite broad public awareness and support, only one-fifth of the Swiss population has completed an AD. Consequently, the roadmap for ACP implementation by the ACP National Task Force calls for the development of digital applications to promote ACP in Switzerland. This study details the development process for the mobile application "iDecide" for AD creation based on the Swiss Medical Association (FMH) AD template. The primary aim is to ensure optimal usability and user satisfaction with the app.

Using a Participatory Action Research (PAR) approach, four research cycles were conducted to create an evidence-based AD creation tool. The iDecide app, published in October 2024 (www.idecide.ch), was reviewed by users through an online survey. The survey evaluated the app's user-friendliness, educational information quality and concordance with ACP goals, measuring 14 items on a 5-point Likert scale.

The PAR approach led to the successful development of the iDecide app for AD creation. The app guides users through the process of drafting their personalised AD. It provides multimedia patient information on the content and value of AD, encourages reflection on personal preferences and promotes communication with surrogate decision-makers and healthcare professionals. The drafted AD is available in both print and in a digital format via an offline QR code. This QR code allows AD information to be stored, shared and accessed when needed. Survey responses from 94 app users indicated high usability, information quality and user satisfaction. On a 5-star rating system, the mean overall rating was 4.69 (SD: 0.57, 95% CI: 4.56-4.81), consistent across age groups. Users rated the app as easy to use and making AD creation more attractive.

While various online forms for AD creation exist in Switzerland, no mobile app has previously enabled the public to complete an AD. iDecide is a ready-to-use AD application, operating without the need for additional infrastructure and freely available to the general public. The tool aligns with the national roadmap for ACP implementation and adheres to key recommendations for digital ACP tool design. It effectively tackles barriers to widespread AD implementation in Switzerland, addressing engagement and accessibility issues. iDecide thus has the potential to empower people to actively engage in their ACP.