The Internet gives patients the opportunity to be better informed, have ownership over their data, and, therefore, be empowered in the medical decision-making process. All of these new forms of patient empowerment through eHealth, however, require the patients’ trust in online service. Existing literature provides a solid foundation regarding the development of trust in social encounters. What is more, the understanding of trust related to more general online services, such as e-commerce is advanced, too. Regarding eHealth in particular, however, there are substantial gaps in the literature. What is more, all existing studies have one pitfall in common. None of them investigates trust as a reciprocal, evolving system that is based on recurring interactions between trustee and truster. Studies either focus on the individual view of the trustee or the truster but fail to analyse the potential dynamics of a trust signal and its evolution.

This led me to research questions that aim to identify trust-evoking factors specific to eHealth, on the one hand, and develop an understanding of the evolution and sustainability of communication between trustee and truster. I applied a mixed-methods approach in order to answer my research questions. This allowed me to use qualitative methods to explore a variety of trust antecedents that are unique to eHealth, develop hypotheses, and then test the derived hypotheses through a quantitative study. One surprising insight of this study is that the risk perception of the overall service offer can determine the level of trust in a service even before entering the website. Risk perception proved to be a more crucial indicator of perceived trustworthiness than presence of trust signals on the website. This allows the conclusion that both researchers and policy makers should differentiate between high-risk and low-risk eHealth services instead of approaching all services under the unifying umbrella of eHealth. Another key finding is that users judge the trustworthiness of eHealth websites depending on their “fit”. For eHealth providers that means that in order to increase trust in their service they need to mimic the offline experience as much as possible.