Protocol of the COVID-19 Health and Adherence Research in Scotland (CHARIS) study: Understanding changes in adherence to transmission-reducing behaviours, mental and general health, in weekly or fortnightly representative samples of the Scottish population

The COVID-19 pandemic has unprecedented consequences on population health, with governments worldwide issuing public health directives which have major impacts on normal living. In the absence of a vaccine, a key way to control the pandemic is through behavioural change: people adhering to transmission-reducing behaviours (TRBs), such as physical distancing, regular hand washing, and wearing face covering, especially when physical distancing is difficult. The application of behavioural science is central to understanding factors that influence adherence to TRBs. Non-adherence may be explained by theories of how people think about the illness (the common-sense model of self-regulation) and/or how they think about the TRBs (social cognition theory and protection motivation theory). In addition, outbreaks of infectious diseases and the measures employed to curb them are likely to have detrimental effects on people’s mental and general health. Therefore, in representative repeated surveys we will apply behavioural theories to model adherence to TRBs, explain variations in adherence, and the effects on mental and general health in the Scottish population from June to November 2020, following the initial outbreak of the COVID-19 pandemic