Theory of Planned Behaviour

The trial focuses on vaping intention because it is treated as a predictor of later behaviour. The intervention is grounded in the Theory of Planned Behaviour. VAPGAMO targets attitudes, subjective norms, perceived behavioural control and behavioural intention. The proposed mechanism links knowledge, social acceptability, refusal self-efficacy and beliefs to reduced vaping intention. TPB identifies attitude, subjective norms, and perceived behavioural control as antecedents of behavioural intention. TPB treats behavioural intention as the proximal predictor of behaviour. The study extends TPB by using its constructs to investigate factors that moderate whether intention becomes action.