The I-Change Model and how it contributes to explaining health behaviour

Abstract

Background: Existing socio-cognitive models have been criticised with regard to their explained variance of health behaviours. The I-Change Model integrates factor of different theories and models. To test its suitability this study tests the I-Change Model with regard to different behaviours. Methods: The study is an overview of several longitudinal quantitative studies with regard to socio-cognitive model testing. SEM and regression analyses were used to investigate the unique contribution of different factors to the predictive value of the model with regard to delayed sexual activity, condom use, smoking cessation, fruit consumption and physical activity. Findings: The first study (delayed sexual activity) indicated that the effect of risk perception on intention and behaviour is mediated by attitude and self-efficacy. The second study (condom use) showed that the effect of knowledge on behaviour is mediated by social norms, attitudes and self-efficacy. The results of the third study (smoking cessation) showed that the effect of the proposed intervention is fully mediated through self-efficacy and coping plans. The fourth study (fruit consumption) illustrated that the effect of planning on behaviour is fully mediated by plan enactment and that this mediation is moderated by self-efficacy, intention and habit. The fifth study (physical activity) demonstrated that the integration of Self-determination Theory added little unique contribution to explaining behaviour but may be useful in understanding underlying processes. Discussion: Despite critics with regard to existing social cognitive models, our studies showed that the integration and testing of models leads to a better understanding of health behaviour.