Aim 1. Cost Effectiveness: We will examine cost effectiveness of the interventions using cost per BMI percentile change as the primary metric as well as the number of outpatient and emergency department visits.

Aim 2. Moderator effects: We hypothesize that children in Group 3 from the upper end of the BMI distribution, i.e., > 95th percentile will show greater change in BMI percentile than their counterparts in Group 2, i.e., baseline weight will interact with Group membership. We will also explore whether parent baseline BMI predicts child response to the intervention.

Aim 3. Mediation effects: We will explore whether changes in child BMI (if observed) are explained by changes in diet and physical activity behaviors assessed by accelerometer (50% subsample), 24hr diet and activity recalls (50% subsample), and the brief behavior screener completed by all parents.

This Project will be conducted with children ages 2-8 and their caregiver recruited from primary care pediatric practices in 4 regions of the PROS (Pediatric Research in Office Settings) Network of the American Academy of Pediatrics (AAP). The counseling will occur with the parent. Children will generally be absent from the room at the time of the counseling. We will work with a total of 30 PROS practices (20 children per practice).

We employ a cluster-randomized design, with PROS practice as the unit of randomization to test two potentially generalizable, behavioral interventions, of varying intensity, compared to a minimal intensity/Usual Care Group.

Group 1 (Usual Care)

Includes determination of BMI percentile at baseline, 1 year, and 2 year follow up for a cohort of youth with a baseline BMI > 85th and < 97th percentile. UC practitioners will also be provided with a series of nutrition and physical activity tip sheets as well as a videotape that demonstrates effective feeding practices developed by CDC for our HLS pilot study. UC pediatricians (PEDs) will also be provided with a 1/2 day study orientation and a brief CME-type workshop addressing obesity treatment guidelines. At the end of the two year study, UC PEDs will be offered the complete MI training and DVD materials.

Group 2 (PED ONLY)

Includes the same assessment points, enrollment criterion and educational materials as UC. In addition, pediatricians (PEDs) will receive 2.0 days of in-person training in MI (1.5 days) and Behavior Therapy (1/2 day) plus 2 telephone-based supervision sessions. PEDs will also receive an interactive DVD MI booster training system focusing on pediatric obesity that will be developed during year 1 of this study. PEDs in Group 2 will schedule 3 proactive counseling sessions with the parent of the index child in Year 1 and 1 additional visit in year 2 year. PEDs will be provided with a behavioral screener adapted from the instrument used in our HLS pilot study, to help families identify and prioritize their behavioral goals. PEDs will be reimbursed $50 per visit for the 4 study visits.

Group 3 (PED+RD)

Includes the same intervention components as Group 2, but adds the involvement of a trained dietitian. RDs will deliver 6 MI-based counseling sessions over 2 years, front loaded with 4 of the sessions in Year 1 and 2 in Year 2. The RD sessions will be delivered both in-person (visit 1) and optionally by telephone. Similar to PEDs, RDs will receive 2.0 days of in-person MI (1.5 days) and Behavior Therapy (1/2 day) training plus 2 telephone-based supervision sessions; and an interactive DVD MI booster training system focusing on pediatric obesity tailored to RDs. RDs will be compensated $50 per in-person visit and $35 for telephone sessions.

We enrolled 633 eligible children whose mean BMI percentile was 92.0 and mean age of 5.1. The cohort was 57% female. Almost 70% of parents reported a household income of $40 000 per year, and 39% had at least a college education. The cohort was 63% White, 23% Hispanic, 7% Black and 7% Asian. Parent self-reported confidence that their child will achieve a healthy weight was on average an 8 (out of 10).

This study will be one of the largest clinical trials of a behavioral intervention to treat pediatric obesity in a primary care setting. Although the outcomes will not be known for 2 years or so, to date, several aspects of the study may nonetheless inform other similar efforts.

• The approach of using, in effect, volunteer clinicians to recruit participants was generally successful. Most practices accrued their sample target of 20 families.
• One rate-limiting step that may impede dissemination of MI in clinical practice is the willingness of practitioners to dedicate sufficient time to attend training programs.
• Although BMI percentile, our primary outcome, did not differ between study groups at baseline, there were several variables, including both demographics and secondary outcomes, for which between-group baseline differences were observed including race, child age, parent gender, parent education, Medicaid status, screen time and sugared beverage intake.
• A practical implication of these findings is that these variables will be included, at least in initial models, as co-variates.