Date of Award

Spring 2009

Document Type


Degree Name

Doctor of Philosophy (PhD)


Psychology and Behavioral Sciences

First Advisor

Tony R. Young


Review of literature indicates that obesity is on the rise nationally and obese individuals are at inherent risk for a variety of comorbid physical, psychological, and social problems which often result in significant functional impairment due to sequelae. Previous research suggests a meaningful association between obesity and greater internalizing difficulties typically manifested by symptoms of depression and anxiety (Faith, Matz, & Jorge, 2002; Scott et al., 2008; Stunkard, Faith, & Allison, 2003; Zhao, Ford, Dhingra, Strine, & Mokdad, 2009). In recent years, there has been emerging interest in exploring the relationship between obesity and individuals with externalizing problems including aggression, oppositionality and hyperactivity (Agranat-Meged et al., 2005; Altfas, 2002; Fornarotto & O'Connell, 2002; Pine et al., 1996). However, few studies have investigated differences among subgroups of obese individuals, possibly masking considerable psychological variability and vulnerability in this population (Onyike, Crum, Lee, Lyketsos, & Eaton, 2003; Scott et al., 2008; Stunkard, Faith, & Allison, 2003). The goal of the current study was to examine causal pathways associated with quality of life and the internalizing and externalizing symptom categories in 206 significantly overweight (Body Mass Index >95th percentile) male and female patients, 6 to 17 years old, presenting for the first time in a multidisciplinary pediatric fitness clinic for treatment. A parent or legal guardian of the participants completed a demographic questionnaire, Pediatric Quality of Life Inventory 4.0 (PedsQL 4.0; Varni, Seid, & Kurtin, 2001), and the Child Behavior Checklist (CBCL; Achenbach 1991 a). The research hypotheses were tested using structural equation modeling as the data analytic technique for measuring and modeling of factors derived from demographic variables, Body Mass Index, health status, as well as child and adolescent quality of life and internalizing and externalizing symptom constructs. A model was developed to examine the pattern of the relationships indicating the hypothesized path and direction of influence. The results indicated that the baseline path model did not fit the data well when goodness of fit indices was assessed. The hypothesis that Quality of Life (QOL) influences Internalizing syndrome scores is supported; however, QOL does not significantly influence Externalizing syndrome scores. It was found that Comorbid Conditions correlate very strongly to Internalizing and Externalizing syndrome scores (p < .001, p < .006) and correlates significantly (p < .05) to age and QOL. These findings underscore the complexity in the relationships among variables as predictors of emotional and behavioral functioning in significantly obese populations. The current study will have important implications in advancing the field of pediatric obesity in the areas of research, education, clinical care, and public policy.