Date of Award
Doctor of Philosophy in Psychology
Joseph S. Rossi
The constructs involved in the Transtheoretical Model (TTM) have been shown to have similar relationships to the Stages of Change across a variety of behaviors. While much work has been done investigating the way the constructs interact cross-sectionally and longitudinally, a completely integrated look at all the constructs of the TTM has not yet been successful. This study integrated all constructs of the TTM related to increase of sun protective behavior across three time points.
The sample used in this study is a portion of a sample collected for three larger, multiple behavior intervention studies. Assessments were collected at baseline, 6-, and 12-month intervals. At baseline, these larger samples included 1472 people in worksites, 1816 parents, and 3875 physician patients at risk for sun exposure. Of these, 341 worksite, 4 31 parent, and 1012 physician had data at all three time points with all necessary variables.
Structural equation modeling was utilized to evaluate panel designs involving seven TTM constructs at baseline, 6-, and 12-month time points. Different models were run within each pre-action Stage of Change. Due to the complexity of the model, a step approach was taken to evaluate the relationships among the constructs.
The Precontemplation group showed relationships between Experiential Processes, Pros and sun protective behavior. The Contemplation and Preparation samples both showed important relationships between Cons and Confidence with behavior. There were more significant paths in the Preparation model indicating greater variance possibly due to more stage movement at follow-up time points.
While not all paths found confirm expectations based on the TTM, there was strong support for the theory. Additional work needs to be done to further investigate these relationships among individual stage transitions or transition groups. A better understanding of the empirical relationships between these constructs will help further understanding of the theory and improve interventions based on the TTM.
Johnson, Janet L., "Integrating the Transtheoretical Model: A Quantitative Analysis in the Area of Sun Exposure" (2001). Open Access Dissertations. Paper 961.