Does perceived behavioural control mediate the relationship between power beliefs and intention?
OBJECTIVE
In order to determine whether the relationship between power beliefs (Sigma(p)) and health-related behavioural intentions is mediated by perceived behavioural control (PBC) we used structural equation modelling of eight cross-sectional data sets.


METHODS
Eight studies that examined health-related behaviours and employed representative samples totalling N = 4663 participants were analysed. All studies involved power belief items derived from pilot testing and employed standard multi-item measures of power beliefs, PBC and intention that were highly reliable.


RESULTS
Confirmatory factor analysis confirmed the discriminant validity of power beliefs, PBC and intention. Structural equation modelling of relevant paths indicated that PBC only partially mediated the relationship between power beliefs and intention (Z(Sobel) = 5.15, p < .001; Z(Baron&Kenny) = 5.16, p < .001). Power beliefs had a significant direct relationship with intention even after PBC had been taken into account.


CONCLUSIONS
The findings undermine Ajzen's contention that PBC mediates the power beliefs-intention relationship and suggests that it is important to employ measures of power beliefs in addition to measures of PBC in order to enhance the prediction of intentions to perform health-risking, or health-promoting, behaviours.
Godin
Gaston
G
Research Group on Psychosocial Aspects of Health-Related Behaviours, Faculty of Nursing Sciences, Laval University, Ste-Foy, Québec, Canada. gaston.godin@fsi.ulaval.ca
Gagné
Camille
C
Sheeran
Paschal
P
D000293:Adolescent; D000328:Adult; D003430:Cross-Sectional Studies; D003469:Culture; D016002:Discriminant Analysis; D005260:Female; D015438:Health Behavior; D006801:Humans; D033182:Intention; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011209:Power, Psychological; D011795:Surveys and Questionnaires