A cluster analytic test of the transtheoretical model applied to exercise behavior
An empirical typology was created to test the application of the Transtheoretical Model (TTM) to exercise behavior. It was reasoned that if a meaningful typology of exercise could be created that depicted construct relationships posited by the TTM, then this would be supportive evidence for the application of the model to understanding behavior change related to exercise. A sample of 342 adults between the ages of 18 and 75 completed a survey through a random telephone interview. The sample was 62% female, 95% white, with an average age of 43 years. The sample was randomly split to perform cluster analysis on each subsample using Ward's method and squared Euclidean distance. The three variables used in the cluster analysis were the Pros of exercise, the Cons of exercise, and Exercise Confidence. The final exercise typology consisted of 6 clusters that were labeled Disengaged, Early, At Risk, Early Action, Maintainers, and Habituated. A series of analyses were conducted to test the internal and external validity of the typology. Two internal validity tests revealed that four of the cluster patterns demonstrated high stability and replicability, while the At Risk and Early Action cluster patterns were less stable. External validity of the clusters was demonstrated with significance testing using the six clusters as levels of a categorical variable to test for differences in five different variable domains: Exercise Behavior, Processes of Change, Stage of Change for Regular Exercise, Stage of Change for other health risks, and demographic variables. Large effect sizes were found for exercise behavior, processes of change, and stage of change. The clusters were also differentiated by stage of change for diet, gender, and perceived health. It was concluded that this series of analyses demonstrated the verisimilitude of the exercise cluster typology and that the clusters potentially represent a limited number of stage subtypes. The results also provide empirical evidence that the spectrum of behavior change can be represented as a series of discrete groups. Issues are discussed pertaining to the application of the exercise typology to developing interventions and recommendations for the use of cluster analysis for exploratory and confirmatory purposes. ^
Psychology, Behavioral|Health Sciences, Recreation|Psychology, Psychometrics
Gregory John Norman,
"A cluster analytic test of the transtheoretical model applied to exercise behavior"
Dissertations and Master's Theses (Campus Access).