An integral part of the game is the trust metric: It tracks the level of trust that the three key stakeholders have in the player, i.e. the science communicator. These groups are: (1) the public, (2) scientists, and (3) authorities. The trust levels of these groups change throughout the game based on how much scientific uncertainty is present in the player’s statements. Changes to the trust metric are calculated as follows:

The shortest possible response a player can select includes only very little scientific uncertainty. In our example, the phrase “according to the current state of knowledge” indicates that the state of knowledge could change in the future. However, the statement does not directly point to uncertainties. Choosing this option increases public trust but decreases trust by scientists and authorities.

Including the second text fragment to the player’s response introduces more scientific uncertainty. In this case the player may add “empirical sciences can never prove the absence of an effect with absolute certainty” to their initial response – explicitly stating the scientific uncertainty. Choosing to include this uncertainty decreases the public’s trust in the player while it increases trust from scientists, with authorities’ trust remaining unchanged.

Adding the third and final text fragment explains how the authorities responsible treat this uncertainty. This increases authorities’ trust while leaving public and scientists’ trust unaffected.

How has this metric been developed? The metric is based on the experiences of science communicators that communicate radiation risks in several European countries. Moreover, text fragments of an earlier version of the game have been tested empirically with a public sample. Test results were also in line with the way the metric is implemented in the game.

Hence, the metric is underpinned by practitioners’ experiences as well as by empirical testing. However, it is important to stress that people can and will react differently to the notion of scientific uncertainty.