Evidence that the type of person affects the strength of the perceived behavioural control-intention relationship

This study examined the role of person type in explaining the relationship between perceived behavioural control and behavioural intentions. Participants (N = 187) completed measures of the theory of planned behaviour (Ajzen, 1991) variables regarding 30 behaviours. Within-participants analyses demonstrated that intentions were more strongly predicted by perceived behavioural control (PBC) than a combination of attitudes and subjective norms among a minority of the sample. When these 'PBC controlled' participants were considered separately, the effects for perceived behavioural control obtained in previous between-participants analyses were augmented. Conversely, when these participants were excluded from the sample, the effects of perceived behavioural control were reduced. PBC control was also modestly associated with dispositional measures of perceived controllability. Overall, the findings indicate that the strength of the perceived behavioural control-intention relationship depends not only on the type of behaviour but also on the type of person.