Planned Behaviour
British Journal of Social Psychology (2001), 40, 471–499 2001 The British Psychological Society
Printed in Great Britain
471
EY cacy of the Theory of Planned Behaviour: A meta-analytic review
Christopher J. Armitage*
Department of Psychology, University of SheYeld, UK
Mark Conner
School of Psychology, University of Leeds, UK
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 signi cant 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 signi cantly 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.
Since Wicker’s (1969) review of research examining the relationship between attitudes and behaviour, and his conclusion that attitudes probably do not predict behaviour, social psychologists have sought to improve the predictive power of attitudes. In recent years, the main approach within this area has been to develop integrated models of behaviour, including additional determinants of behaviour such as social norms
Printed in Great Britain
471
EY cacy of the Theory of Planned Behaviour: A meta-analytic review
Christopher J. Armitage*
Department of Psychology, University of SheYeld, UK
Mark Conner
School of Psychology, University of Leeds, UK
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 signi cant 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 signi cantly 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.
Since Wicker’s (1969) review of research examining the relationship between attitudes and behaviour, and his conclusion that attitudes probably do not predict behaviour, social psychologists have sought to improve the predictive power of attitudes. In recent years, the main approach within this area has been to develop integrated models of behaviour, including additional determinants of behaviour such as social norms