Abstract
Objective
To compare the utility of Protection Motivation Theory (PMT) and the Theory of Planned Behaviour (TPB) for understanding diversity in adherence to COVID-19 behavioural guidelines.
Methods and measures
A representative sample (N = 600) completed two online questionnaires: One that included measurements of PMT and TPB components that predict behaviour, and another (after one week) consisting of adherence to COVID-19 behavioural guidelines. TPB was represented by a single model, while PMT was represented by three models: Model 1, which did not include a measure of protection motivation; Model 2, which included protection motivation – represented by behavioural intentions; and Model 3, which was similar to Model 2 and included a direct link from self-efficacy to behaviour.
Results
The TPB model displayed the best fit-to-complexity ratio (i.e. information criterion), and its capacity to explain adherence was similar to PMT Models 1 and 2, but lower than Model 3.
Conclusion
The findings highlight the need to reach a consensus regarding the definition and measurement of protection motivation. While the TPB model exhibited superior fit-to-complexity ratio, variance was better explained when self-efficacy was included, and interventions may benefit from targeting different constructs depending on the context.
Disclosure statement
The researchers declare no conflict of interest.
Data availability statement
Data available on request from the authors.
Notes
1 Consequently, the model assumed all variables to be correlated, except for perceived response costs with perceived vulnerability and severity, and the correlation between self-efficacy and perceived vulnerability.