This study evaluates and compares the efficacy of professional versus peer-based delivery of family-based treatment for childhood overweight and obesity in elementary school aged children. Families will be randomized to receive treatment from professionals or to receive treatment from professionally-trained peer interventionists. Some parents will then be invited to serve as peer interventionists for the next group of families.

The high prevalence of pediatric overweight and obesity in the U.S. necessitates the development of efficacious, but cost-effective and easily disseminable interventions that improve and sustain better pediatric weight outcomes. Accumulated evidence finds initial and long-term efficacy of moderate-to-high intensity (>25 contact hours) family-based treatment (FBT) for elementary school-aged children, but such treatment is prohibitively expensive because of high personnel costs (delivery by behavioral health professionals) and therefore limited in availability, reach, and impact. Very few overweight/obese children receive evidence-based treatment to improve their weight status or health.

The pilot data suggest a new model, peer-based delivery FBT with FBT-treated parents trained and subsequently delivering FBT to other families, is feasible and demonstrates initial efficacy. This delivery model could dramatically reduce FBT costs and increase FBT availability. Preliminary data also suggest that serving as a peer interventionist may also benefit the peers themselves and their children in better sustaining their own weight outcomes. The present study aims to provide a more definitive test of the short- and long-term efficacy of peer- versus professionally-delivered FBT on child weight outcomes. Embedded in this comparison is an examination of the feasibility of peer-based FBT delivery, investigating the impact of serving as a peer interventionist on the peers' own and their child's long- term weight status, and a more comprehensive examination of differential costs of professional- versus peer- based FBT delivery.

The present study will also test potential dissemination and sustainability by examining the efficacy of peer-delivered FBT among peer interventionists who themselves received FBT from other peers and not from professional interventionists. Moderation of treatment outcome is also examined, focusing on peer interventionist and child characteristics. This multi-phase trial will enroll 304 families with 7-11 year old overweight/obese children in multiple sites throughout the region, and include short-term (post-treatment) and long-term (up through 1 year after treatment cessation) assessments. This investigation of an innovative approach that could significantly reduce FBT delivery costs, while also improving the maintenance of treatment effects, is critical to improving the health of the many already overweight children at risk for chronic disease.

Inclusion Criteria:

• Child age: 7-11 years at time of enrollment
• Overweight child: at or above 85th percentile for age- and gender-specific BMI.
• At least one overweight parent (BMI≥ 25.0).
• Parent is willing and able to actively participate in treatment including willingness to serve as a peer interventionist following treatment.
• Must live within 50 miles of the treatment center.

Exclusion Criteria:

• Current enrollment in another weight control program for the participating child or parent.
• The participating parent is pregnant.
• Thought disorder, suicidality, or substance abuse disorder in either the participating parent or the participating child.
• Inability of the child to comprehend English at a 1st-grade level or participating parent to comprehend English at an 8th-grade level.
• Physical disability or illness in either the participating parent or the child that precludes moderate intensity physical activity.
• Medication regimen for the child that affects his or her weight.
• Conditions known to promote obesity in the participating child (e.g. Prader-Willi).
• Diagnosed eating disorder (i.e., anorexia nervosa, bulimia nervosa, binge eating disorder) in either parent (participating and nonparticipating) and/or the participating child.