Andreas Mojzisch

Building on the seminal studies of Solomon Asch and Muzafer Sherif, recent research has advanced our understanding of the mechanisms underlying social influence by applying a diffusion model analysis. Here, we combined the social identity approach to social influence with a diffusion model analysis to unravel the mechanisms underlying social influence. In particular, we aimed to disentangle whether the difference between in‐group and out‐group influence on perceptual decision‐making is driven by a judgmental bias (i.e., changes in decision criteria) or a perceptual bias (i.e., changes in the uptake of sensory information). Preregistered analyses indicated that in‐groups exerted stronger social influence than out‐groups because in‐groups induced a stronger perceptual bias than out‐groups. This finding is in line with the single process assumption of the social identity approach because it implicates that the single process driving social influence (i.e., self‐categorisation) translates into a change in a single subprocess of decision‐making (i.e., biased information uptake). In conclusion, our results highlight that our theoretical understanding of social influence can be expanded by integrating the social identity approach with a diffusion model analysis.

Job demands can negatively affect sleep. However, previous studies have provided inconclusive results regarding the mediating role of work‐related rumination in this relationship. Integrating prolonged activation theory with the challenge‐hindrance framework, we hypothesized that – on a day level – hindrance demands, but not challenge demands, are negatively associated with sleep quality and sleep duration via work‐related rumination. We tested this assumption in a 14‐day ambulatory assessment study with a sample of employees ( N = 175). As predicted, we found that only hindrance demands, but not challenge demands, are related to sleep quality via work‐related rumination. No relationships with sleep duration were found for any type of job demands.

Background and Aims Previous research has pointed to the potential of workplace interventions addressing alcohol consumption. However, there is still no systematic overview of the effects of these interventions. Therefore, we aimed to quantify the effectiveness of workplace interventions addressing alcohol use by conducting a meta‐analysis. Methods A systematic literature search for randomized controlled trials of workplace alcohol interventions published between 1995 and 2020 was conducted in five databases. Studies were included if they were performed in the workplace and reported universal or selective interventions aiming for alcohol use reduction. Primary outcomes were any measures of alcohol use. Standardized mean effect sizes were used to calculate the meta‐analytic random‐effects‐model. Additional analyses were carried out to identify potential moderators and to examine the amount of heterogeneity and publication bias. Results Twenty studies with 4484 participants were integrated into the meta‐analysis. Results revealed a significant overall mean effect indicating a reduction of alcohol use in favor of the treatment group ( d = −0.16, 95% CI = [−0.2715; −0.0511]). Heterogeneity within the data structure was found to be moderate to substantial ( I 2 = 75.9%, Q‐test P < 0.001, τ 2 = 0.0375). Additional moderator analyses only showed a significant effect for length of measurement period ( P = 0.049). Conclusions Alcohol‐related prevention programs conducted in the workplace have a statistically significant and favorable effect on alcohol consumption. Although the overall mean effect is considered to be small, it underlines the effectiveness of workplace interventions targeting a reduction in alcohol use.

Over the past 3 years, employees have constantly witnessed how their organizations have responded to the challenges posed by the COVID‐19 pandemic. Here, we hypothesize that employees' perceptions of the COVID‐19 safety climate of their organization positively affect their vaccine readiness. To examine the underlying mechanisms of this effect, we use a self‐perception theory lens. Thus, we hypothesize that an organization's COVID‐19 safety climate affects employees' COVID‐19 vaccine readiness through employees' adherence to COVID‐19 guidelines. We conducted a time‐lagged study over the time span of 1 year ( N = 351) to test our hypotheses. In general, results support our hypotheses. In particular, results showed that perceived COVID‐19 safety climate assessed at an early stage of the pandemic (April 2020, when no vaccines were available) predicted employees' COVID‐19 vaccine readiness more than a year later. In line with self‐perception theory, this effect was mediated by employees' adherence to COVID‐19 guidelines. The present study provides theoretical insight into the underlying mechanisms of organizational climate on employees' attitudes. From a practical perspective, our results suggest that organizations are a powerful lever for promoting vaccine readiness.