[Show abstract][Hide abstract] ABSTRACT: In preterm infants, poor postnatal growth is associated with adverse neuro-cognitive outcomes; conversely rapid postnatal growth is supposedly harmful for future development of metabolic diseases.
In this systematic review, observational studies reported consistent positive associations between postnatal weight or head growth and neuro-cognitive outcomes, however there was limited evidence from the few intervention studies. Evidence linking postnatal weight gain to later adiposity and other cardiovascular disease risk factors in preterm infants was also limited. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Curve matching is a new big data technique to predict an outcome given earlier measurements. Here we apply curve matching to predict the future growth of a specific child, the target child. The method searches in large datasets of longitudinal growth data for other children who are similar to the target child in terms of factors that influence growth. The observed growth curves of these matched children provide valuable insights into the future growth of the target child. The TNO Groeivoorspeller (TNO Growth Predictor) plots the expected growth of the target child, as well as the uncertainty of the prediction. Curve matching is a general technique that can also be used for other health measures. The key requirement is the availability of relevant longitudinal data on the outcome and its determinants.
Nederlands tijdschrift voor geneeskunde 07/2015; 159:A8547.
[Show abstract][Hide abstract] ABSTRACT: Objectives: To study trends in height of Turkish and Moroccan immigrant children living in The Netherlands, to investigate the association between height and background characteristics in these children, and to calculate height-for-age-references data for these groups. Design: Nationwide cross-sectional data collection from children aged 0 to 18 years by trained professionals in 1997 and 2009. The study population consisted of 2,822 Turkish 2,779 Moroccan, and 13,705 Dutch origin children in 1997and 2,548 Turkish, 2,594 Moroccan, and 11,255 Dutch origin children in 2009. Main outcome measures: Mean height in cm, and mean height standard deviation scores. Results: In 2009, mean height at the age of 18y was similar for Turkish and Moroccan children: 177 cm for boys and 163 cm for girls, which was 2 to 3 cm taller than in 1997. Still, Turkish and Moroccan adolescents were 5.5 cm (boys) to 7 cm (girls) shorter than their Dutch peers. No significant differences were found in mean height standard deviation scores across the educational level of the parents, geographical region, primary language spoken at home, and immigrant generation. Conclusions: While the secular height increase in Dutch children came to a halt, the trend in Turkish and Moroccan children living in The Netherlands continued. However, large differences in height between Turkish and Moroccan children and Dutch children remain. We found no association with the background characteristics. We recommend the use of the new growth charts for children of Turkish and Moroccan origin who have a height-for-age below -2SD on the growth chart for Dutch children.
PLoS ONE 05/2015; 10(5):e0124686. DOI:10.1371/journal.pone.0124686 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Introduction Lifestyle Triple P is a general parenting intervention which focuses on preventing further excessive weight gain in overweight and obese children. The objective of the current study was to assess the effectiveness of the Lifestyle Triple P intervention in the Netherlands. Method We used a parallel randomized controlled design to test the effectiveness of the intervention. In total, 86 child-parent triads (children 4-8 years old, overweight or obese) were recruited and randomly assigned (allocation ratio 1:1) to the Lifestyle Triple P intervention or the control condition. Parents in the intervention condition received a 14-week intervention consisting of ten 90-minute group sessions and four individual telephone sessions. Primary outcome measure was the children' s body composition (BMI z-scores, waist circumference and skinfolds). The research assistant who performed the measurements was blinded for group assignment. Secondary outcome measures were the children's dietary behavior and physical activity level, parenting practices, parental feeding style, parenting style, and parental self-efficacy. Outcome measures were assessed at baseline and 4 months (shortterm) and 12 months (long-term) after baseline. Multilevel multiple regression analyses were conducted to determine the effect of the intervention on primary and secondary outcome measures. Results No intervention effects were found on children's body composition. Analyses of secondary outcomes showed positive short-term intervention effects on children's soft-drink consumption and parental responsibility regarding physical activity, encouragement to eat, psychological control, and efficacy and satisfaction with parenting. Longer-term intervention effects were found on parent 's report of children's time spent on sedentary behavior and playing outside, parental monitoring food intake, and responsibility regarding nutrition. Conclusion Although the Lifestyle Triple P intervention showed positive effects on some parent reported child behaviors and parenting measures, no effects were visible on children's body composition or objectively measured physical activity. Several adjustments of the intervention content are recommended, for example including a booster session.
PLoS ONE 04/2015; 10(4):e0122240. DOI:10.1371/journal.pone.0122240 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: This study was conducted to (1) identify improvements in care quality and well-being of patients with chronic obstructive pulmonary disease in the Netherlands and (2) investigate the longitudinal relationship between these factors.
This longitudinal study was conducted among patients diagnosed with chronic obstructive pulmonary disease enrolled in the Kennemer Lucht care programme in the Netherlands. Biomarker data (lung capacity) were collected at patients' health care practices in 2012. Complete case analysis was conducted, and the multiple imputation technique allowed us to report pooled results from imputed datasets.
Surveys were filled out by 548/1303 (42%) patients at T0 (2012) and 569/996 (57%) remaining participants at T1. Quality of care improved significantly (p < 0.05). Analyses adjusted for well-being at T0, age, educational level, marital status, gender, lung function and health behaviours showed that patients' assessments of the quality of chronic care delivery at T0 (p < 0.01) and changes therein (p < 0.001) predicted patients' well-being at T1.
These results clearly show that the quality of care and changes therein are important for the well-being of patients with chronic obstructive pulmonary disease in the primary care setting.
To improve quality of care for chronically ill patients, multicomponent interventions may be needed.
International journal of integrated care 04/2015; 15:e028. · 1.50 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Twenty-five scientists met at Aschauhof, Altenhof, Germany, to discuss various aspects of the complex network of modern health screening, focusing on current scientific topics including medical sciences, human biology, and mathematics; on problems in implementing these results at the practical level of physicians, nurses, technicians, and engineers; and the level of administrative and political decisions. Whereas major scientific advancements have been published in the understanding and the bio-statistical evaluation of anthropometric screening parameters such as serial measurements of height and weight for preventive medical check-ups, BMI screening and surveillance in schools, etc., the implementation of these advancements into current health screening concepts, strategies and decision-making is poor. Fear of discrimination, misperception of body image, behavioural responses and political concerns, meanwhile dominate and negatively interfere with the implementation of recent scientific results into public health screening concepts and practices.
Pediatric endocrinology reviews: PER 03/2015; 12(3):323-32.
[Show abstract][Hide abstract] ABSTRACT: Accurate calculations of testicular volume standard deviation (SD) scores are not currently available. We constructed LMS-smoothed age-reference charts for testicular volume in healthy boys.
The LMS method was used to calculate reference data, based on testicular volumes from ultrasonography and Prader orchidometer of 769 healthy Dutch boys aged six months to 19 years. We also explored the association between testicular growth and pubic hair development and data were compared to orchidometric testicular volumes from the 1997 Dutch nationwide growth study.
The LMS-smoothed reference charts showed that no revision of the definition of normal onset of male puberty - from nine to 14-years-of-age - was warranted. In healthy boys, the pubic hair stage SD scores corresponded with testicular volume SD scores (r=0.394). However, testes were relatively small for pubic hair stage in Klinefelter syndrome and relatively large in immunoglobulin superfamily member 1 deficiency syndrome.
The age-corrected SD scores for testicular volume will aid in the diagnosis and follow up of abnormalities in the timing and progression of male puberty and in research evaluations. The SD scores can be compared with pubic hair SD scores to identify discrepancies between cell functions that result in relative microorchidism or macroorchidism. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: To derive regional weight-for-age growth references to help optimize age-based dosing of antimalarials in Africa, the Americas, South-East Asia and the Western Pacific.
A weight-for-age database was constructed from pre-existing population-based anthropometric data obtained from household surveys and research groups. It contained data collected between 1995 and 2012 on 1 263 119 individuals (909 368 female, 353 751 male) older than 14 days and younger than 50 years in 64 malaria-endemic countries. Regional growth references were generated using a generalized additive model for location, scale and shape by combining data with varying distributions from a range of sources. Countries were weighted by their population at risk of malaria to enable references to be used in optimizing the dosing of antimalarials.
Large differences in weight-for-age distributions existed between the regions and between the regions and global growth standards. For example, the average adult male from the Americas weighed 68.1 kg - 6.0 kg more than males in South-East Asia and the Western Pacific (average: 62.1 kg). For adult women, the difference was over 10.4 kg: the average was 60.4 kg in the Americas and 50.0 kg in South-East Asia and the Western Pacific.
There were substantial variations in weight-for-age growth curves between malaria-endemic areas. The growth reference charts derived here can be used to guide the evidence-based optimization of aged-based dosing regimens for antimalarials and other drugs often prescribed by age.
Bulletin of the World Health Organisation 02/2015; 93(2):74-83. DOI:10.2471/BLT.14.139113 · 5.09 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Current pooling rules for multiply imputed data assume infinite populations.
In some situations this assumption is not feasible as every unit in the
population has been observed, potentially leading to over-covered population
estimates. We simplify the existing pooling rules for situations where the
sampling variance is not of interest. We compare these rules to the
conventional pooling rules and demonstrate their use in a situation where there
is no sampling variance. Using the standard pooling rules in situations where
sampling variance should not be considered, leads to overestimation of the
variance of the estimates of interest, especially when the amount of
missingness is not very large. As a result, populations estimates are
over-covered, which may lead to a loss of statistical power. We conclude that
the theory of multiple imputation can be extended to the situation where the
sample happens to be the population. The simplified pooling rules can be easily
implemented to obtain valid inference in cases where we have observed
essentially all units and in simulation studies addressing the missingness
[Show abstract][Hide abstract] ABSTRACT: Background:
Although children both at the upper and lower tail of the body mass index (BMI) distribution are at greater health risk, relatively little is known about the development of thinness prevalence rates in developed countries over time. We studied trends in childhood thinness and assessed changes in the BMI distribution since the onset of the obesity epidemic.
Growth data from 54 814 children aged 2-18 years of Dutch, Turkish and Moroccan origin living in The Netherlands were used. Anthropometric measurements were performed during nationwide cross-sectional growth studies in 1980 (only Dutch), 1997 and 2009. Prevalence rates of thinness grades I, II and III were calculated according to international cut-offs. BMI distributions for 1980, 1997 and 2009 were compared.
Since 1980, thinness (all grades combined) reduced significantly from 14.0% to 9.8% in children of Dutch origin, but the proportion of extremely thin children (grade III) remained constant. Thinness in children of Moroccan origin decreased significantly from 8.8% to 6.2% between 1997 and 2009. No significant difference was observed in children of Turkish origin (5.4% in 1997 vs. 5.7% in 2009). Thinness occurred most often in children aged 2-5 years. There were no differences between boys and girls. The BMI distribution widened since 1980, mainly due to an upward shift of the upper centiles.
Since the onset of the obesity epidemic, prevalence rates of thinness decreased. However, we found a small but persistent group of extremely thin children. More research is needed to gain insight into their health status.
The European Journal of Public Health 08/2014; 25(2). DOI:10.1093/eurpub/cku130 · 2.59 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We propose a new multiple imputation technique for imputing squares. Cur-
rent methods yield either unbiased regression estimates, or preserve data re-
lations. No method, however, seems to deliver both, which limits researchers
in the implementation of regression analysis in the presence of missing data.
Besides, current methods only work under a MCAR mechanism. Our method
for imputing squares uses a polynomial combination. The proposed method
yields both unbiased regression estimates, whilst at the same time preserving
the quadratic relations in the data for both MAR and MCAR mechanisms.
[Show abstract][Hide abstract] ABSTRACT: Abstract Background: People from Asian populations are generally shorter than other ethnic groups. It is unknown if current universal height references are suitable for affluent South Asian children in the Netherlands. Aims: To develop height-for-age charts for contemporary South Asian children aged 0-20 years living in the Netherlands, to evaluate secular trends, and to compare the charts with current Asian Indian, Dutch and WHO references. Subjects and methods: A population-based study measured 3315 South Asian children aged 0-20 years between 2007-2010. Among this cohort, 6876 measurements were taken. Another 7388 measurements were taken of a historical cohort of 1078 children born between 1974-1976 (aged 0-18 years). Results: An upward trend in height was observed for South Asian children living in the Netherlands between 1992-2010. The height-for-age charts of the South Asian historical cohort were similar to current Asian Indian charts. South Asian children in the Netherlands were shorter than their Dutch contemporaries at every age; and these differences increased further during adolescence. Compared to the WHO height-for-age references, there were considerable discrepancies in height, with curves intersecting twice. Conclusion: The discrepancies between the South Asian and Dutch and WHO height-for-age references indicate differences in growth patterns between the source populations.
Annals of Human Biology 06/2014; 42(1):1-7. DOI:10.3109/03014460.2014.926988 · 1.27 Impact Factor