Using routinely collected growth data to assess a school-based obesity prevention strategy

Area of Science:

• Pediatric Obesity Research
• Public Health Interventions
• School-Based Health Programs

Background:

• School-based anti-obesity interventions show inconsistent results.
• Previous studies reported a beneficial effect of a specific strategy on student weight status.
• This study re-evaluated that strategy using growth screening data.

Purpose of the Study:

• To re-evaluate the effectiveness of a school-based nutrition education intervention on childhood obesity.
• To assess changes in body mass index (BMI) Z-scores and overweight/obesity prevalence.
• To investigate incidence, remission, and long-term effects of the intervention.

Main Methods:

• A 2-year cluster-randomized trial involving 10 K-8 schools (5 intervention, 5 control).
• Analysis of student height and weight data for 6 consecutive school years.
• Mixed-effects linear regression for BMI Z-scores and conditional logistic regression for overweight/obesity prevalence.

Main Results:

• No significant difference in mean BMI Z-score increase between intervention (0.10) and control (0.09) groups.
• Overweight/obesity prevalence increased by 3% in both groups, with no significant intervention effect.
• No significant intervention effect on incidence, remission, or long-term outcomes.

Conclusions:

• The nutrition education intervention did not confirm earlier findings of effectiveness when applied to the entire target population.
• Discrepancies may be due to volunteer bias in prior evaluations or measurement error in routinely collected data.
• Routinely collected data for the entire student population did not support the intervention's efficacy.