ABSTRACT
Varying degrees of restrictions on public behaviour were imposed by different national governments. In some cases, their strategies and tactics changed during the course of the pandemic. This was true in the United Kingdom where the government changed its approach early in the outbreak after epidemiological modelling warned of high death rates from COVID-19 without more stringent interventions that restricted public behaviour. At this point, the nudge approach was side-lined. This also encouraged the consideration of different models of behaviour change. Among the most widely used models in this context is the theory of planned behaviour. This model highlights the importance of internal cognitive processes such as attitudes and beliefs concerning the behaviour to be changed, beliefs about what other people might be doing and beliefs about personal efficacy to embrace specific changes. In this chapter, research is reviewed that emerged from different countries and populations during the pandemic that adopted this theoretical model to guide study design and data interpretation. Although this theory is not perfect and has not gone unchallenged, it was found to be helpful in providing some insights into factors that can influence how different populations reacted to pandemic-related restrictions on their behaviour.
