Self-efficacy: the third factor besides attitude and subjective norm as a predictor of behavioural intentions

When explaining (health) behaviour much attention is paid to attitudes and subjective norms. It is assumed that self-efficacy expectations will significantly increase the prediction of behavioural intentions. Therefore, the self-efficacy concept from Bandura's social learning theory has been integrated together with the two factors of the Fishbein-Ajzen model within one model to explain behavioural intentions. Results of a hierarchical regression analysis support the abovementioned hypothesis: attitudes and subjective norms are significant predictors of the intention (not) to smoke, but self-efficacy expectations add significantly to the prediction of the intention. Self-efficacy has also a direct effect on behaviour, after controlling for intention. Our interpretation is that in this study self-efficacy probably highly reflects the actual control or the skills of the adolescents. This study also supports the results of Ajzen and Madden (1986) who indicated that perceived behavioural control expectations increased the predictions of behavioural intentions. Furthermore, it appears that non-smoking adolescents have higher self-efficacy expectations towards non-smoking than smokers.