Efficacy of the Theory of Planned Behaviour: A meta‐analytic review

Abstract

The Theory of Planned Behaviour (TPB) has received considerable attention in the literature. The present study is a quantitative integration and review of that research. From a database of 185 independent studies published up to the end of 1997, the TPB accounted for 27% and 39% of the variance in behaviour and intention, respectively. The perceived behavioural control (PBC) construct accounted for significant amounts of variance in intention and behaviour, independent of theory of reasoned action variables. When behaviour measures were self-reports, the TPB accounted for 11% more of the variance in behaviour than when behaviour measures were objective or observed (R2s = .31 and .21, respectively). Attitude, subjective norm and PBC account for significantly more of the variance in individuals' desires than intentions or self-predictions, but intentions and self-predictions were better predictors of behaviour. The subjective norm construct is generally found to be a weak predictor of intentions. This is partly attributable to a combination of poor measurement and the need for expansion of the normative component. The discussion focuses on ways in which current TPB research can be taken forward in the light of the present review.

A mixed-method systematic review and meta-analysis of mental health professionals' attitudes toward smoking and smoking cessation among people with mental illnesses

“…The relationship between attitudes/beliefs, intentions and behaviour is well established (e.g. 44, 45), and health professionals are no exception 46. This review highlights the potential for such attitudes to present a barrier to integrate smoking cessation interventions effectively into treatment for mental illnesses and substance use disorders.…”

Is the intention–behaviour gap greater amongst the more deprived? A meta‐analysis of five studies on physical activity, diet, and medication adherence in smoking cessation

“…Our findings are compatible with the meta‐analysis by Webb and Sheeran (2006), which concluded that the link between intention and behaviour is much weaker than previously assumed (cf. Armitage & Conner, 2001). The authors found that interventions that had a large effect on individuals' intentions only produced a small change in behaviour that can be attributed to the intentional control of behaviour.…”

Promoting fruit and vegetable consumption. Testing an intervention based on the theory of planned behaviour

“…A large number of studies provide support for the utility of the model in the prediction of behaviour (Armitage & Conner, 2001;Godin & Kok, 1996). In the context of fruit and vegetable intake, the model has been reported to account for an average of 41% of the variance in intention and 45% of the variance in behaviour (Guillaumie, Godin, & Vézina-Im, 2010).…”

“…The extent to which PBC has a direct influence on behaviour is often thought to reflect an individual's actual behavioural control over the target behaviour (Fishbein & Ajzen, 2010). Given the difficulty in directly assessing actual behaviour control for most health related behaviours, PBC is used as a proxy for actual behaviour control the majority of TPB based studies (Armitage & Conner, 2001;Fishbein & Ajzen, 2010;Godin & Kok, 1996).…”

“…The extent to which PBC has a direct influence on behaviour is often thought to reflect an individual's actual behavioural control over the target behaviour (Fishbein & Ajzen, 2010). Given the difficulty in directly assessing actual behaviour control for most health related behaviours, PBC is used as a proxy for actual behaviour control the majority of TPB based studies (Armitage & Conner, 2001;Fishbein & Ajzen, 2010;Godin & Kok, 1996).A large number of studies provide support for the utility of the model in the prediction of behaviour (Armitage & Conner, 2001;Godin & Kok, 1996). In the context of fruit and vegetable intake, the model has been reported to account for an average of 41% of the variance in intention and 45% of the variance in behaviour (Guillaumie, Godin, & Vézina-Im, 2010).…”