Longitudinal Curves for Behaviors of Children Diagnosed with A Brain Tumor

• Main Author: Chai, Huayan
• Format: Others
• Published: Digital Archive @ GSU 2007
• Subjects: Mixed Model; Fractional Polynomial Transformation; Gompertz Model; Press; Mathematics
• Online Access: http://digitalarchive.gsu.edu/math_theses/22; http://digitalarchive.gsu.edu/cgi/viewcontent.cgi?article=1021&context=math_theses

Change in adaptive outcomes of children who are treated for brain tumors is examined using longitudinal data. The children received different types of treatment from none to any combinations of three treatments, which are surgery, radiation and chemotherapy. In this thesis, we use mixed model to find the significant variables that predict change in outcomes of communication skill, daily living skills and socialization skill. Fractional polynomial transformation method and Gompertz method are applied to build non-linear longitudinal curves. We use PRESS as the criterion to compare these two methods. Comparison analysis shows the effect of each significant variable on adaptive behaviors over time. In most cases, model with Gompertz method is better than that with Transformation method. Significant predictors of change in adaptive outcomes include Time, Gender, Surgery, SES classes, interaction between Time and Radiation, interaction between Time and Gender, interaction between Age and Gender.