Longitudinal relationships among transtheoretical model constructs for smokers in the precontemplation and contemplation stages of change

Background: This study examined the pattern, direction, and magnitude of longitudinal relationships among the constructs involved in the Transtheoretical Model (TTM). Purpose: The goal was to explore within-TTM relationships to create an integrated structural model that adequately represents the change process. Method: Data were collected as part of a representative general adult population study in Germany. A total of 688 smokers in the precontemplation and contemplation stages of change were assessed two times, 6 months apart, with respect to the TTM constructs. Structural equation modeling was used and a step approach was employed to evaluate the relationships between cognitive-affective processes, behavioral processes, the pros and cons of smoking, and self-efficacy, stratified for baseline stage of change. Results: The model-building process resulted in two final structural equation models detailing longitudinal TTM relationships for precontemplation and contemplation. A structural invariance test showed that the precontemplation model also held for the contemplation sample and visa versa. Conclusions: The TTM constructs can be integrated in a longitudinal structural model. The findings provide empirical support for specific relationships that are posited in the TTM framework. However, differing relationships between TTM constructs for precontemplation and contemplation could not be established.