Application of the theory of planned behaviour in behaviour change interventions: A systematic review

This paper reviews studies explicitly applying the Theory of Planned Behaviour (TPB) to behaviour change interventions. A systematic and multiple search strategy identified 30 papers, describing 24 distinct interventions. Studies were rarely explicit about use of the TPB. The TPB was mainly used to measure process and outcome variables and to predict intention and behaviour, and less commonly to develop the intervention. Behaviour change methods were mostly persuasion and information, with increasing skills, goal setting, and rehearsal of skills used less often. When reported, half of the interventions were effective in changing intention, and two-thirds in changing behaviour, with generally small effect sizes, where calculable. Effectiveness was unrelated to use of the theory to develop interventions. Evidence about mediation of effects by TPB components was sparse. The TPB may have potential for developing behaviour change interventions, but more comprehensive studies are needed that compare the utility of the TPB with other social cognition models and behavioural techniques.