Prevalence of overweight and obesity among primary school students in Batna: Comparison of IOTF, WHO, CDC, and French classifications in a cross-Sectional study

Objective: This study aims to assess the prevalence of overweight and obesity among children aged 6 to 11 years attending public primary schools in Batna, based on a comparative analysis of four reference systems: IOTF, WHO, CDC, and the French reference. Methods: A descriptive cross-sectional survey was conducted during the 2018–2019 school year, involving 3172 students from 20 schools and 159 classes across the three municipalities of Batna. Clinical assessment was carried out in small groups, following a preparatory phase that included awareness-raising among children, staff training, equipment setup, and calibration. Data collected included anthropometric measurements, pubertal stage assessment, and blood pressure readings. Statistical analysis was performed using SPSS software, version 26. Results: The prevalence of overweight, including obesity, varied depending on the reference used: 21.3% according to IOTF (with 7.8% classified as obese), 26.8% according to WHO (12.7% obese), 22.8% according to CDC (12.2% obese), and 20.8% according to the French reference. Severe obesity affected 1.4% of students according to the IOTF 2012 thresholds, and 3.3% according to WHO 2007 thresholds, with a significant male predominance in both cases (p < 0.05). Morbid obesity was found in 0.79% of students. A strong and statistically significant positive linear correlation was observed between BMI and waist circumference (r = 0.880, p < 10⁻⁴), as well as between BMI and waist-to-height ratio (r = 0.848, p = 0.01). Conclusion: The WHO and CDC references tend to overestimate the prevalence of overweight and obesity in children from Batna, due to lower classification thresholds compared to the IOTF and the French reference. These findings highlight the importance of specifying the reference used, which will help refine comparative analysis with results from other studies.