To determine the extent to which a clinical intervention based on the Chronic Care Model (CCM), compared with the usual care control condition, results in a smaller age-associated increase in body mass index (BMI) over a 1 year intervention (primary outcome) and a 1 1/2-year follow-up period.

Overweight in the preschool age group is prevalent, increasing, and of consequence. During the last 30 years in the U.S., the prevalence of overweight among youth has dramatically increased. Overweight in young children is associated with later overweight, with childhood conditions such as hyperlipidemia, hypertension, and type II diabetes, and with higher morbidity and mortality in adulthood.

Along with the long-term risks associated with overweight in the preschool age group, there come unique opportunities to intervene and alter the subsequent course of health and disease for these individuals. These regular visits allow both detection of elevated BMI levels and opportunities for intervention.

The overall goal of this research is to assess a comprehensive, innovative, primary care practice change intervention to prevent obesity among children age 2 through 5 years at elevated risk of obesity. To achieve this goal, we will conduct a cluster-randomized controlled trial in 10 pediatric practices of Harvard Vanguard Medical Associates, a large multi-site group practice in eastern Massachusetts with a track record of research collaboration.

We will randomize five health centers to the intervention condition, and five health centers to the control (usual care) condition. The intervention will consist of state-of-the-science approaches to changing dietary, activity, and inactivity behaviors among the children.

The intervention period will be 1 year, followed by a 1 1/2 year maintenance follow-up period. Frequency of visits will be every 6 weeks for the first 6 months, and every 6 months after that. Participating families will complete a telephone-administered interview at baseline and all follow-up timepoints. There will be 3 types of measurements: 1) measurements made by the clinical staff that will also be used for outcomes in the research study (only height and weight); 2) measurements made by clinicians for feedback during counseling sessions, which will not be used for study outcomes; and 3) measurements made by the research staff for study outcomes and processes.

Inclusion Criteria:

• Age 2.0 through 5.9 years receiving primary care in a multi-site group practice
• BMI > 95th percentile for age and sex, or 85th - 95th percentile if at least one parent is overweight

Exclusion Criteria:

• Child currently enrolled in a formal weight management program
• Child is in foster care
• Chronic conditions that may limit our ability to measure height and weight or that may interfere with their growth, physical activity, or dietary recommendations