Since 1858, an increase of mean stature has been observed in the Netherlands, reflecting the improving nutritional, hygienic, and health status of the population. In this study, stature, weight, and pubertal development of Dutch youth, derived from four consecutive nationwide cross-sectional growth studies during the past 42 y, are compared to assess the size and rate of the secular growth change. Data on length, height, weight, head circumference, sexual maturation, and demographics of 14,500 boys and girls of Dutch origin in the age range 0-20 y were collected in 1996 and 1997. Growth references for height and weight were constructed with a method that summarizes the distribution by three smooth curves representing skewness (L curve), the median (M curve), and coefficient of variation (S curve). The relationship between height and demographic variables was assessed by multivariate analysis. Reference curves for menarche and secondary sex characteristics were estimated by a generalized additive model using a logit transformation. A positive secular growth change has been present in the past 42 y for children, adolescents, and young adults of Dutch origin, although at a slower rate in the last 17 y. Height differences according to region, educational level of child and parents, and family size have remained. In girls, median age at menarche has decreased by 6 mo during the past four decades to 13.15 y. Environmental conditions have been favorable for many decades in the Netherlands, and the positive secular change in height has not yet come to a halt, in contrast to Scandinavian countries. Main contributors to the increase in height may be improved nutrition, child health, and hygiene, and a reduction of family size.

Objectives-To compare the distribution of body mass index (BMI) in a national representative study in The Netherlands in 1996-7 with that from a study in 1980. Methods-Cross sectional data on height, weight, and demographics of 14 500 boys and girls of Dutch origin, aged 0-21 years, were collected from 1996 to 1997. BMI references were derived using the LMS method. The 90th, 50th, and 10th BMI centiles of the 1980 study were used as baseline. Association of demographic variables with BMI-SDS was assessed by ANOVA. Results-BMI age reference charts were constructed. From 3 years of age onwards 14-22% of the children exceeded the 90th centile of 1980, 52-60% the 50th centile, and 92-95% the 10th centile. BMI was related to region, educational level of parents (negatively) and family size (negatively). The −0.9, +1.1, and +2.3 SD lines in 1996-7 corresponded to the adult cut oV points of 20, 25, and 30 kg/m 2 recommended by the World Health Organisation/ European childhood obesity group. Conclusion-BMI age references have increased in the past 17 years. Therefore, strategies to prevent obesity in childhood should be a priority in child public health. (Arch Dis Child 2000;82:107-112) Keywords: body mass index; reference values; Netherlands; obesity Body mass index (BMI; weight/height 2 ) as a measure for underweight and overweight is widely accepted. For adults, a pragmatic classification system exists, based on associations between body mass index and all cause mortality.1 Recently, BMI cut oV values for adults were redefined and divided into six classes: < 18.5 kg/m 2 , underweight; 18.5-24.9 kg/m 2 , ideal weight; 25.0-29.9 kg/m 2 , preobese; 30.0-34.9 kg/m 2 , obese class I; 35.0-39.9 kg/m 2 , obese class II; and > 40 kg/m 2 , obese class III.

Many psychosomatic and psychosocial health problems follow an episode of bullying victimization. These findings stress the importance for doctors and health practitioners to establish whether bullying plays a contributing role in the etiology of such symptoms. Furthermore, our results indicate that children with depressive symptoms and anxiety are at increased risk of being victimized. Because victimization could have an adverse effect on children's attempts to cope with depression or anxiety, it is important to consider teaching these children skills that could make them less vulnerable to bullying behavior.

We investigated pubertal development of 4019 boys and 3562 girls Ͼ8 y of age participating in a cross-sectional survey in The Netherlands and compared the results with those of two previous surveys. Reference curves for all pubertal stages were constructed. The 50th percentile of Tanner breast stage 2 was 10.7 y, and 50% of the boys had reached a testicular volume of 4 mL at 11.5 y of age. Median age at menarche was 13.15 y. The median age at which the various stages of pubertal development were observed has stabilized since 1980. The increase of the age at stage G2 between 1965 and 1997 is probably owing to different interpretations of its definition. The current age limits for the definition of precocious are close to the third percentile of these references. A high agreement was found between the pubic hair stages and stages of pubertal (genital and breast) development, but slightly more in boys than in girls. Menarcheal age was dependent on height, weight, and body mass index. At a given age tall or heavy girls have a higher probability of having menarche compared with short or thin girls. A body weight exceeding 60 kg (ϩ1 SDS), or a body mass index of Ͼ20 (ϩ1 SDS), has no or little effect on the chance of having menarche, whereas for height such a ceiling effect was not observed. In conclusion, in The Netherlands the age at onset of puberty or menarche has stabilized since 1980. Height, weight, and body mass index have a strong influence on the chance of menarche. The development and first appearance of secondary sexual characteristics can be regarded as a reflection of the overall physiologic development in adolescence (1). The continuous process of pubertal development is usually subdivided into discrete numerical stages, as proposed by Marshall and Tanner (2, 3).The assessment of pubertal stages in the individual child or adolescent in the clinic is only useful if recent and reliable reference data from the same population are available for comparison. As in many European countries a positive secular trend with regard to height, accompanied by a decrease of the age at onset of puberty (1, 4, 5), has been observed, nationwide reference data should be collected at 10-to 20-y intervals. If the age at onset of puberty would indeed decrease, the definition of precocious and delayed puberty should be adjusted. In fact, in the United States it was recently proposed to revise the guidelines for the evaluation of girls with precocious puberty (6, 7).Besides clinical reasons, there are also scientific reasons to study pubertal development in a large population-based sample of healthy children and adolescents. First, it is unclear whether the secular trend with regard to body stature is invariably associated with a trend toward earlier pubertal development. Second, there are few data on the association between the markers of the maturation process of the hypothalamopituitary-gonadal axis (breast development in girls and genital stage in boys) and the occurrence of pubic hair. One would suspect that the agreement be...