Quantitive methods for assessing change: Application to condom use

This study attempts to understand more about how to quantitatively assess longitudinal change within the Transtheoretical Model applied to the area of condom use among college students. A total of 215 sexually active male and female undergraduate students completed both assessments one month apart. Measurement development was conducted on the Condom Use URICA scale, which was then used in a cluster analysis . A four cluster solution was reliably replicated across two random samples (R=.99), and the clusters were then examined in terms of their external validity using MANOVAs. The four clusters showed significant differences on variables associated with the Transtheoretical Model, psycho-attitudinal variables and a behavioral measure of condom use. In addition, the four cluster solution was compared to the Stages of Condom Use that were assessed using an algorithm approach . Latent Transition Analysis was used to assess an appropriate model of natural movement through the Stages of Condom Use for men and women . Precontemplation was found to be the most stable stage for the entire sample, as well as for the sample of women only. However , the model for men only found Preparation to be the most stable. All three of the resulting models found relapse to be an important aspect of the model. Longitudinal predictors of stage movement were examined using logistic regression. Models on the entire sample indicated that high endorsement of Eroticizing Condoms predicted progression. Models specific to both men and women found that high Self-Esteem was associated with greater regression. Lastly, Longitudinal Structural Modeling was used to further understand the relationship between Stages of Condom Use and other variables associated with both the TTM and the Multifaceted Model of HIV Risk in Women. The only predictors of Stage one month later were the Pros and Cons of condom use. This also served as an application of longitudinal "step-modeling" to a limited real world data set. Each of the separate types of analyses provide insight into different questions surrounding the analysis of change within the context of condom use. These results can help guide the development of interventions focusing on increasing condom use among undergraduate students. Acknowledgment This project is a culmination of four years of learning and research at the Cancer Prevention Research Center and within the Psychology department. I would like to thank all of those individuals who have influenced this project. However, it would be impossible to thank all those who have provided inspiration and support during this process. I would , however , like to acknowledge a few individuals. First , I would like to acknowledge my dissertation committee. Dr. Lisa Harlow , my major professor, has provided me with enthusiasm , encouragement, support , and guidance throughout my graduate career. It was her work that brought me to this area, and she has been a wonderful role-model for me. I only hope that in the future I can provide the same amount of understanding and inspiration for a student. Dr. Colleen Redding has not only acted as a member of my committee, but as a supervisor in my work at the center. She has been a strong influence on my development and thinking in the area of behavior science. Dr. Janet Hirsch , who has always forced me to look more closely at the implications of my work and helped me to articulate them. Dr. Wayne V elicer has influenced both my own work, and my work through he center and has encouraged me to expand my methodological skills. Finally , Dr. Phil Clark who allowed me to "dabble " in the area of public policy and has greatly impacted the way I look at the area of health. I would also like to acknowledge Dr. James Prochaska , Dr. Joseph Rossi , Dr. Laurie Ruggiero, and Dr. Robert Laforge who have provided me with wonderful supervision in a variety of areas. I must also thank the faculty and staff at the Cancer Prevention Research Center, especially Kathy Meier and Elaine Taylor who are always there when you need them, for whatever reason.