Conspiracy mentality and health-related behaviour during the COVID-19 pandemic: a multiwave survey in Italy

Objectives This study aimed to (1) explore the changes in conspiracy mentality across the four waves of the COVID-19 pandemic; (2) assess the relationship between conspirative mentality and psychological/behavioural variables; (3) identify the predictors of conspirative mentality; and (4) explore the effect of conspirative mentality on COVID-19 protective behaviour. Study design This was a multiwave survey. Methods A total of 10,013 Italian individuals, aged 18–70 years, were assessed across the four waves (from January to May 2021) through online survey. We collected information about the sociodemographic characteristics of participants, personal experiences of COVID-19 infection, trust, COVID-19 protective behaviours, COVID-19 risk perception, arousal, auto-efficacy, resilience and well-being. Conspiracy mentality was assessed with the Conspiracy Mentality Questionnaire. The statistical analyses included exploratory factorial analyses, Pearson correlations and multiple linear regressions. Results The conspiracy mentality score during the COVID-19 pandemic was medium–high (mean 59.0 on a 0–100 scale) and slightly increased from 58.2 to 59.9 across months, in parallel with a slight decrease in trust in health institutions and scientific informational sources. Individuals aged >35 years, poorly educated and particularly scared about their financial situation were at risk of showing higher levels of conspirative mentality. Higher levels of conspirative mentality were risk factors for low levels of COVID-19 protective behaviours. Conclusions Clear and effective communication may improve trust in health institutions and informational sources, decrease conspirative theories and increase compliance with protective behaviour.