Predicting household food waste reduction using an extended theory of planned behaviour

Identifying the antecedents of household food waste reduction is an important step in the development of effective and efficient interventions. This prospective study tested the utility of applying an extended theory of planned behaviour (TPB) model to household food waste reduction. At baseline, participants (N = 279) completed a questionnaire designed to measure the following cognitive constructs derived from the extended TPB model: intention, attitude, subjective norm, perceived behavioural control, self-identity, anticipated regret, moral norm and descriptive norm. At follow-up, participants (N = 204) completed a questionnaire assessing their household food waste behaviour. The extended TPB model accounted for a substantial amount (64%) of the variance in intention, with attitude, subjective norm, perceived behavioural control, self-identity and anticipated regret emerging as significant linear predictors. Furthermore intention significantly predicted the likelihood that participants had reduced their household fruit and vegetable waste at follow-up; however, the amount of variance in behaviour accounted for by the TPB model was relatively small (5%). Results demonstrate the utility of applying an extended theory of planned behaviour model to predict motivation and - to a lesser extent - behaviour, in the context of household fruit and vegetable waste reduction.