['The prevalence of obesity has reached alarming levels in recent years. Neck circumference (NC) has been shown to be an indicator of central adiposity.', 'The purpose of this study was to analyse whether NC can be used to determine overweight and obesity in Han Chinese children.', 'In 2011, anthropometric measurements were gathered in a cross-sectional, population-based study of 2847 Han children aged 7-12 years. Overweight and obesity were defined according to the 2004 Chinese obesity task force definition. Receiver operating characteristic curve analyses were conducted to assess the accuracy of NC as a diagnostic test for elevated body mass index (BMI) (overweight and obesity).', 'The prevalence of overweight and obesity in boys was 18.0% and 26.0%, respectively, and 11.7% and 15.7%, respectively, for girls. The mean NC in boys was significantly greater than in girls (29.2 ± 3.1 cm vs 28.1 ± 2.8 cm, p < 0.001). NC was significantly correlated with age, BMI and waist circumference in both boys and girls (p < 0.001 for all comparisons). NC cut-off values for elevated BMI were between 27.4~31.3 cm in boys and 26.3~31.4 cm in girls. The sensitivities were 75.5~86.7% in boys and 80.0~92.5% in girls. The specificities were 73.9~91.7% in boys and 74.7~93.3% in girls.'] Is neck circumference an accurate and simple index for evaluating overweight and obesity in Han children?