In this paper, we analyze a two-level latent variable model for longitudinal data from the National Growth of Health Study where surrogate outcomes or biomarkers and covariates are subject to missingness at any of the levels. A conventional method for efficient handling of missing data is to reexpress the desired model as a joint distribution of…

Body mass index classification, physical activity (PA), and sedentary behaviors were compared in adolescents with autism spectrum disorder (ASD) to typically developing adolescents. Participants included 42,747 adolescents (ASD, n = 915) from the 2011-2012 National Survey of Children's Health. After controlling for covariates, adolescents were…

About one-quarter of Canadian adults and more than one-third of adults in the United States are obese. Obese children are at risk of becoming obese adults and can experience immediate health consequences such as psychosocial stress, elevated blood pressure and cholesterol, and abnormal glucose tolerance. Monitoring trends in childhood obesity is…

Background: This study attempted to determine whether state laws regulating low nutrient, high energy-dense foods and beverages sold outside of the reimbursable school meals program (referred to as "competitive foods") are associated with children's weight status. Methods: We use the Classification of Laws Associated with School…

Background: Income disparities in US youth in academic achievement appear to widen during the summer because of discontinued learning among children from lower-income households. Little is known about whether behavioral risk factors for childhood obesity, such as diet and physical activity, also demonstrate a widening difference by income when…

Childhood obesity is a major public health problem associated with many adverse health outcomes in adulthood. During 2011-2012, nearly 17% of children and adolescents were obese. Weight status misperception occurs when the child's perception of their weight status differs from their actual weight status based on measured height and weight.…

Obesity, physical activity, and sedentary behavior in childhood are important indicators of present and future health and are associated with school-related outcomes such as academic achievement, behavior, peer relationships, and self-esteem. Using logistic regression models that controlled for gender, age, ethnicity/race, and socioeconomic…

Background: Among school-aged youth, we sought to identify characteristics associated with (1) exceeding screen time recommendations (ie, television/videos/video games more than 2 hours/weekday), and (2) exceeding screen time recommendations, the presence of a television in the bedroom, and obesity. Methods: Using 2007 National Survey of…

Afterschool programs have continued to grow in sophistication, increase their offerings and improve quality. As the role of afterschool programs has evolved from primarily providing a safe and supervised environment to a resource that provides a host of supports for their students, programs have become valuable partners in helping students reach…

Afterschool programs continue to make advances when it comes to providing students with nutritious foods, keeping them physically fit and promoting health. Such programs have great potential to help prevent obesity and instill lifelong healthy habits, serving more than 10 million children and youth across America, with more than 19 million more…

This dissertation evaluates the impact of elementary school policies on child health behaviors and obesity in the United States. Two chapters address nutrition policies, two chapters address physical activity policies, and a final chapter estimates the health care cost savings associated with a decline in childhood obesity prevalence. The use of…

National surveys that have tracked weight and physical activity in the United States for more than 40 years have shown a continuing increase in the number of overweight children and adolescents. Overweight children and adolescents are showing an increase in diseases related to overweight: Type II diabetes, cardiovascular disease, hypertension, and…