Objective: To evaluate how public perceptions and trust in government communications affected the adoption of protective behaviour in Singapore during the coronavirus disease 2019 (COVID-19) pandemic .

Methods: We launched our community-based cohort to assess public perceptions of infectious disease outbreaks in mid-2019 . After the first case of COVID-19 was reported in Singapore on 23 January, we launched a series of seven COVID-19 surveys to both existing and regularly enrolled new participants every 2 weeks . As well as sociodemographic properties of the participants, we recorded changing responses to judge awareness of the situation, trust in various information sources and perceived risk . We used multivariable logistic regression models to evaluate associations with perceptions of risk and self-reported adopted frequencies of protective behaviour . Findings: Our cohort of 633 participants provided 2857 unique responses during the seven COVID-19 surveys . Most agreed or strongly agreed that information from official government sources (99.1% ; 528/533) and Singapore-based news agencies (97.9% ; 522/533) was trustworthy . Trust in government communication was significantly associated with higher perceived threat (odds ratio, OR : 2.2; 95% confidence interval, CI : 1.6-3.0), but inversely associated with perceived risk of infection (OR : 0.6; 95% CI : 0.4-0.8) or risk of death if infected (OR : 0.6; 95% CI : 0.4-0.9). Trust in government communication was also associated with a greater likelihood of adopting protective behaviour . Conclusion: Our findings show that trust is a vital commodity when managing an evolving outbreak . Our repeated surveys provided real-time feedback, allowing an improved understanding of the interplay between perceptions, trust and behaviour.