Participation in science communication is often proposed as a strategy to enhance public trust in science (Gascoigne et al., 2022; Kappel & Holmen, 2019). However, empirical evidence on the participation-trust link remains scarce and mixed (Bedessem et al., 2021, 2023). Moreover, the field lacks a theoretical understanding of why and how participation might affect trust. This results in a practical dilemma for science communicators and citizen science practitioners, who must allocate resources without knowing which participatory features are most likely to build trust.
To address this gap, the present contribution explores psychological distance as a potential mechanism that mediates participation's effects on trust. According to Construal Level Theory, perceived psychological distance – the subjective experience of removal from an entity along social, temporal, spatial or hypothetical dimensions – shapes how we mentally represent that entity (Trope & Liberman, 2010). Recent work on Psychological Distance to Science (PSYDISC) shows that lower perceived PSYDISC is linked to more favourable science evaluations and higher trust (Većkalov et al., 2024; Rutjens & Hornsey, 2025).
We explore if participatory practices within science communication – specifically, co-design of science communication materials – may enhance trust precisely by reducing PSYDISC. Co-design requires participants to actively transform abstract scientific content into concrete representations in a setting of shared decision-making (Gascoigne et al., 2022), which leads to a shift in construal from abstract to concrete regarding scientific content (hypothetical distance) and reframes scientists from distant experts to collaborators (social distance). Given the bidirectional relationship between PSYDISC and construal level, this could bring science closer, thereby potentially increasing perceptions of trustworthiness (on the dimensions of expertise, benevolence, integrity) and trust, conceptualised as willingness to be vulnerable (Besley & Tiffany, 2023; Hendriks et al., 2015; Mayer et al., 1995).
While field evidence from citizen science suggests that direct collaboration can reduce psychological distance and foster trust (Vegt et al., 2023), no experimental research has yet systematically examined whether: (a) psychological distance causally affects trust, (b) participation reduces psychological distance, or (c) distance reduction mediates participation's effects on trust. With two complementary preregistered experiments we aim to test these proposed pathways.
Study 1 (N = 1,442) employed a 2×2 between-subjects vignette design manipulating social distance (scientist engaging with public vs. only with scientists) and hypothetical distance (research findings presented as applicable vs. theoretical). Results indicated that reduced hypothetical distance was associated with higher perceived expertise (F (1, 1438) = 9.71, p = .002; d = 0.16) and an increased willingness to be vulnerable (F (1, 1436) = 23.78, p < .001, d =.26). Neither social distance framing, nor an interaction between both dimensions showed significant effects. These findings suggest differential relevance of distance dimensions for trust, highlighting perceived applicability as key.
Study 2 (ongoing, target N = 800) extends this approach from vignettes to a simulated participatory context. Following a baseline assessment, participants complete an online intervention one week later, collaborating with a fictional scientist to co-design communication materials about antimicrobial resistance. We manipulate social and hypothetical distance in a 2×2 design across eight scientist profiles. The design combines a pre-post intervention with four embedded process measures after every co-design task to track the trajectory of psychological distance. This enables a process-oriented mediation analysis to test whether changes in psychological distance account for changes in trust.
Together, these studies contribute both to the theoretical advancement and practical application of participatory science communication. Theoretically, we seek to better understand how participation relates to trust by focusing on its potential to reduce psychological distance as one underlying mechanism enhancing trust.
Practically, this line of research could inform evidence-based design principles for participatory initiatives. For example, if reducing hypothetical distance proves crucial in the intervention study, practitioners could strategically enhance trust by using targeted participatory tasks that emphasize the concrete relevance and tangibility of science. This would move beyond the assumption that participation alone builds trust toward understanding which features actually drive this effect.