Using three different screening methods to study overweight and simple obesity among children under age 7 in Ningbo city / 中华流行病学杂志

ABSTRACT

Objective To investigate the occurrence of simple obesity among children under age 7 in Ningbo and to analyze the data regarding body mass index (BMI) from overweight screening under different standards. Methods Randomized cluster sampling was adopted and 64 038 children under 7 years old in Ningho were chosen and their length/height and weight were measured but pathological and secondary obesity cases were excluded. According to the Standardized Height and Weight set by WHO, more than 10% referring to overweight and more than 20% referring to obesity. Moreover, results of this study were compared with growth standards with WHO' s 2006 and IOTF standards. Results According to the Standardized Height and Weight set by WHO, the prevalence rates of overweight and obesity of children under age 7 were 4.25% and 2.88%. The ratio for boys were 4.45% and 3.01%, while for girls as 3.86% and 2.56%, with significant difference (P<0.01). Data showed that the rates for overweight and obesity increased along with age, reaching 11.84% and 9.68% for boys and 10.14% and 9.46% for girls at the age of 6. The ratios of overweight/obesity among different age groups and sex were 1.15-1.941. The critical value for P85, P95 were lower than the standards set by WHO and IOTE The rates for overweight and obesity for latter were 9.72%, 2.83% and 6.11%, 0.55% respectively. Conclusion Early childhood is the key period for obesity prevention, with boys in particular. Prevention and control for childhood obesity should be included in the programs for children' s health. Value of classification standards for the BMI screening of overweight and obesity for children under age 7 should be established in no time.