Moderating role of attitudinal ambivalence within the theory of planned behaviour.

The present study examined the moderating role of attitudinal ambivalence within the theory of planned behaviour (TPB). Attitude, subjective norm, perceived behavioural control (PBC), behavioural intentions and self-reported behaviour were assessed in relation to 20 healthy eating behaviours in a prospective questionnaire design in 232 members of the general public in the UK. Between-participants univariate and multivariate analyses indicated attitude-behaviour and PBC-behaviour relationships to be weaker in higher ambivalence compared to lower ambivalence respondents. These effects were confirmed in within-participants analyses. The findings are discussed in terms of the role of ambivalence in furthering our understanding of relationships in the TPB.