Summary: In the coronavirus “infodemic,” people are exposed to official recommendations but also to potentially dangerous pseudoscientific advice claimed to protect against COVID‐19. We examined whether irrational beliefs predict adherence to COVID‐19 guidelines as well as susceptibility to such misinformation. Irrational beliefs were indexed by belief in COVID‐19 conspiracy theories, COVID‐19 knowledge overestimation, type I error cognitive biases, and cognitive intuition. Participants (N = 407) reported (1) how often they followed guidelines (e.g., handwashing, physical distancing), (2) how often they engaged in pseudoscientific practices (e.g., consuming garlic, colloidal silver), and (3) their intention to receive a COVID‐19 vaccine. Conspiratorial beliefs predicted all three outcomes in line with our expectations. Cognitive intuition and knowledge overestimation predicted lesser adherence to guidelines, while cognitive biases predicted greater adherence, but also greater use of pseudoscientific practices. Our results suggest an important relation between irrational beliefs and health behaviors, with conspiracy theories being the most detrimental.

Economic inequality is associated with preferences for smaller, immediate gains over larger, delayed ones. Such temporal discounting may feed into rising global inequality, yet it is unclear whether it is a function of choice preferences or norms, or rather the absence of sufficient resources for immediate needs. It is also not clear whether these reflect true differences in choice patterns between income groups. We tested temporal discounting and five intertemporal choice anomalies using local currencies and value standards in 61 countries (N = 13,629). Across a diverse sample, we found consistent, robust rates of choice anomalies. Lower-income groups were not significantly different, but economic inequality and broader financial circumstances were clearly correlated with population choice patterns.

Low self-control is associated with increased consumption of alcohol, tobacco, and unhealthy food. This systematic review aimed to assess whether individual differences in self-control modify the effectiveness of interventions to reduce consumption of these products, and hence their potential to reduce consumption amongst those whose consumption is generally greater. Searches of six databases were supplemented with snowball searches and forward citation tracking. Narrative synthesis summarised findings by: consumption behaviour (alcohol, tobacco, food); psychological processes targeted by the intervention (reflective, non-reflective, or both); and study design (experiment, cohort, or cross-sectional). Of 54 eligible studies, 22 reported no evidence of modification, 18 reported interventions to be less effective in those with low self-control, and 14 reported interventions to be more effective in those with low self-control. This pattern did not differ from chance. Whilst self-control often influenced intervention outcomes, there was no consistent pattern of effects, even when stratifying studies by consumption behaviour, intervention type, or study design. There was a notable absence of evidence regarding interventions that restructure physical or economic environments. In summary, a heterogeneous, low-quality evidence base suggests an inconsistent moderating effect of low self-control on the effectiveness of interventions to change consumption behaviours.

The potential benefits of travelling across national borders to obtain medical treatment include improved care, decreased costs and reduced waiting times. However, medical travel involves additional risks, compared to obtaining treatment domestically. We review the publicly-available evidence on medical travel. We suggest that medical travel needs to be understood in terms of its potential risks and benefits so that it can be evaluated against alternatives by patients who are seeking care. We propose three domains -quality standards, informed decision-making, economic and legal protection - in which better evidence could support the development of medical travel policies.

Objective: Wine glass size may influence perceived volume and subsequently purchasing and consumption. Using a larger glass to serve the same portions of wine was found to increase wine sales by 9.4% (95% CI 1.9, 17.5) in a recent study conducted in one bar. The current study aimed to replicate this previous work in two other bars using a wider range of glass sizes. To match the previous study, a repeated multiple treatment reversal design, during which wine was served in glasses of the same design but different sizes, was used. The study was conducted in two bars in Cambridge, England, using glass sizes of 300, 370, 510 ml (Bar 1) and 300 and 510 ml (Bar 2). Customers purchased their choice of a 750 ml bottle, or standard UK measures of 125, 175 or 250 ml of wine, each of which was served with the same glass. Results: Bar 1 Daily wine volume (ml) purchased was 10.5% (95% CI 1.0, 20.9) higher when sold in 510 ml compared to 370 ml glasses; but sales were not significantly different with 300 ml vs. 370 ml glasses (6.5%, 95% CI −5.2, 19.6). Bar 2 Findings were inconclusive as to whether daily wine purchased differed when using 510 ml versus 300 ml glasses (−1.1%, 95% CI −12.6, 11.9). These results provide a partial replication of previous work showing that introducing larger glasses (without manipulating portion size) increases purchasing. Understanding the mechanisms by which wine glass size influences consumption may elucidate when the effect can be expected and when not. Trial registration This study is a replication study, based on the procedure set out in the trial registration for the study that it attempts to replicate (ISRCTN registry: ISRCTN12018175)