Randomized Controlled Trial of BMI Screening: Effects on Obesity, Disparities, and Body Satisfaction

The Fit Study is a three-year, cluster-randomized controlled trial that will evaluate the impact of school-based body mass index (BMI) screening and reporting on childhood obesity and psychosocial outcomes. This study will take place during the 2014-15, 2015-16, and 2016-17 school years. Seventy-nine schools across California will be randomized to one of three groups: 1) BMI screening and reporting, 2) BMI screening, and 3) no BMI screening or reporting (control). Schools randomized to Groups 1 and 2 will conduct height and weight measurements annually with their 3rd-8th grade students. Group 1 and 2 schools will also administer the five fitness assessments (mile run or PACER test, curl-ups, push-ups, trunk lift, and sit and reach) annually with their 5th-8th grade students. In the fall of Years 2 and 3, Group 1 schools will mail a report home to parents with students' results from the previous spring. All 3rd and 4th grade parents will receive a report with BMI results only. Investigators will randomize the parents of 5th-8th grade students to receive a report that provides BMI results only or one that provides BMI results with results from the five fitness assessments. Schools randomized to Group 3 will not conduct height and weight measurements with their students during Years 1 and 2.

Each fall, investigators will administer a survey to 4th-8th grade students from all schools. This survey will assess weight-based teasing, feelings of stigmatization, and weight-control behaviors among students. The student survey will also ask questions about students' experiences having their heights and weights measured at school. During all years, investigators will mail a survey home a subsample of parents to assess parent behaviors related to their child's physical activity and nutrition, as well as parent reactions to the BMI report. Finally, schools will complete a survey in Spring 2017 to assess their nutrition- and physical activity-related policies and programs.