Most of the family-centered studies that include school-aged children or adolescents are treatment rather than prevention studies. Family-based approaches to weight control were first developed more than 35 years ago when it was demonstrated that a more structured “lifestyle modification” approach that included family members was more effective for children’s weight loss rather than standard weight reduction approaches [53]. For this chapter, 13 studies are reviewed, eight representing shorter-term studies. Most of the existing family-centered obesity treatment interventions for children and adolescents are based on the landmark work of Epstein [39, 54, 55] and Golan [45]. Family-centered studies that produced shorter-term impacts on school-aged children or adolescents are described below and reported in Table 12.2. Following this section is a description of five studies from the United States and abroad that report longer-term results from family-centered studies for school-aged children and/or adolescents.

Shelton and colleagues [68] assessed the impact of a 3-month, parent-based (n = 43 families) behavioral intervention on BMI of overweight and obese children in Australia. Although some younger children were included in this study (ages ranged from 3 to 10 years), the average child’s age was between 7 and 8 years. In four brief sessions, the intervention promoted healthy family lifestyle changes by addressing nutrition, physical activity, motivation, and behavior management strategies. At the end of the 3 months, children in the intervention group experienced a significant decrease in BMI, but the intervention had no significant effect on parental BMI.

In a randomized controlled trial on child weight loss, Boutelle and colleagues [56] evaluated whether a 5-month standardized, behavioral, parent-only treatment program was inferior to a standardized parent-plus-child program. Eighty parents and their overweight or obese children (aged 8–12 years) were recruited in Minnesota and San Diego and randomly assigned to either a parent-plus-child or a parent-only group. This intervention adapted Epstein’s Traffic Light Diet protocol [69] and included strategies for increasing physical activity, behavioral change skills, (viz., self-monitoring of targeted behaviors, positive reinforcement, stimulus control, preplanning, and modeling), and parenting skills specific for use with children who are overweight. Information presented to children in the parent-plus-child group was similar to that taught to the parents, but was presented in an age-appropriate manner. Weight outcomes of children and parents assessed at baseline, 5-month post-intervention, and at an 11-month follow-up showed that the parent-only group was not inferior to the parent-plus-child group in either child weight loss or parent weight loss. Further exploratory analyses [70] also showed that across both study groups, parent BMI was the only significant predictor of child weight, with a 1 BMI unit reduction in parent weight associated with a 0.255 reduction in child BMI.

In another study using the Epstein Traffic Light Diet protocol, Kalarchian and colleagues [64] evaluated the efficacy of a 6-month, clinic-based, family-centered, behavioral intervention on reducing the weight of 192 severely obese children aged 8–12 years. Families were randomized into either an intervention group that received the family-based intervention, or a control group that received a standard care approach that consisted of two consultation sessions to help them develop individual nutrition plans based on the Traffic Light Diet. Adult and child groups met separately, and each group was presented with similar materials. Overweight adults were encouraged, but not required, to lose weight. At 6 months, the intervention was associated with greater decreases in child percent overweight than the decreases for the children in the control group. Intent-to-treat analyses showed that the intervention was associated with a significant 7.58 % decrease in child percent overweight at 6 months, compared to a 0.66 % decrease for the control group, but differences between the two groups were not significant at 12 or 18 months. In addition, children who attended at least 75 % of the intervention sessions maintained decreases in percent overweight through 18 months, while those who attended less than 75 % of the intervention sessions did not. Parent BMI was reduced significantly in the treatment groups at both the 6- and 12-month measurement periods.

In a family-centered intervention, Janicke and colleagues [63, 71] assessed the effects on the weight of underserved children of Project STORY (Sensible Treatment of Obesity in Rural Youth), a 4-month, family-based, behavioral intervention, and a parent-only behavioral intervention delivered through rural cooperative extension service offices. Participants were 93 overweight or obese children (aged 8–14 years) and their parents recruited from four underserved rural counties in North Central Florida. Participants were randomly assigned to one of three groups: a family-based group in which both children and parents were targeted as active agents of change, a parent-only group that targeted parents as the agents of change, and a waitlist control group that received the intervention following the final follow-up assessments. In general, Project STORY focused on five things: building healthier dietary habits via a modified version of Epstein and colleagues’ Traffic Light Diet, increasing moderate intensity physical activity via a pedometer step program, setting goals for reducing sedentary activities, establishing a healthier weight status, and building positive self-worth in participants. Behavioral strategies used in delivering the Project STORY included self-monitoring, goal setting, stimulus control, positive reinforcement, modeling, role playing, and portion size control. At the 4-month assessment, children in the parent-only intervention group showed a greater decrease in BMI z score than children in the waitlist control group. No significant differences, however, were found in BMI z scores between the family-based intervention group and the waitlist control group. At the 10-month follow-up, children in the parent-only and family-based intervention groups showed greater decreases in BMI z score from before treatment (baseline) than the waitlist control group. The intervention did not have any significant effect on parental BMI change score at either month 4 or 10.