Sample 1
The first sample was drawn from children participating in a school-based randomized clinical trial on reducing television viewing. Twelve elementary schools from 2 ethnically diverse elementary school districts in northern California participated in this study. All third-grade children enrolled in the schools in September 1999 were eligible to participate. During telephone interviews, parents were informed of the opportunity to participate in 24-h dietary recalls and physical activity monitoring. If they were interested in having their child participate, they were mailed information, including a consent form, and contacted to schedule an initial interview. All children recruited at baseline (fall1999)andadditionalchildrenfromthesame12schoolswho were recruited into the control group during the spring 2000 data-collection period were included in the sample. This sample is referred to as the third-grade sample.