Anthropometric standardisation and quality control protocols for the construction of new, international, fetal and newborn growth standards: the INTERGROWTH-21st Project.
ABSTRACT: The primary aim of the INTERGROWTH-21(st) Project is to construct new, prescriptive standards describing optimal fetal and preterm postnatal growth. The anthropometric measurements include the head circumference, recumbent length and weight of the infants, and the stature and weight of the parents. In such a large, international, multicentre project, it is critical that all study sites follow standardised protocols to ensure maximal validity of the growth and nutrition indicators used. This paper describes in detail the anthropometric training, standardisation and quality control procedures used to collect data for these new standards. The initial standardisation session was in Nairobi, Kenya, using newborns, which was followed by similar sessions in the eight participating study sites in Brazil, China, India, Italy, Kenya, Oman, UK and USA. The intraobserver and inter-observer technical error of measurement values for head circumference range from 0.3 to 0.4 cm, and for recumbent length from 0.3 to 0.5 cm. These standardisation protocols implemented at each study site worldwide ensure that the anthropometric data collected are of the highest quality to construct international growth standards.
Project description:When breastfeeding is not possible, infants are fed formulas in which lipids are usually of plant origin. However, the use of dairy fat in combination with plant oils enables a lipid profile in formula closer to breast milk in terms of fatty acid composition, triglyceride structure and cholesterol content. The objectives of this study were to investigate the impact on growth and gastrointestinal tolerance of a formula containing a mix of dairy lipids and plant oils in healthy infants.This study was a monocentric, double-blind, controlled, randomized trial. Healthy term infants aged less than 3 weeks whose mothers did not breastfeed were randomly allocated to formula containing either: a mix of plant oils and dairy fat (D), only plant oils (P) or plant oils supplemented with long-chain polyunsaturated fatty acids (PDHA). Breastfed infants were included in a reference group (BF). Anthropometric parameters and body composition were measured after 2 and 4 months. Gastrointestinal tolerance was evaluated during 2 day-periods after 1 and 3 months thanks to descriptive parameters reported by parents. Nonrandomized BF infants were not included in the statistical analysis.Eighty eight formula-fed and 29 BF infants were enrolled. Gains of weight, recumbent length, cranial circumference and fat mass were similar between the 3 formula-fed groups at 2 and 4 months and close to those of BF. Z-scores for weight, recumbent length and cranial circumference in all groups were within normal ranges for growth standards. No significant differences were noted among the 3 formula groups in gastrointestinal parameters (stool frequency/consistency/color), occurrence of gastrointestinal symptoms (abdominal pain, flatulence, regurgitation) or infant's behavior.A formula containing a mix of dairy lipids and plant oils enables a normal growth in healthy newborns. This formula is well tolerated and does not lead to abnormal gastrointestinal symptoms. Consequently, reintroduction of dairy lipids could represent an interesting strategy to improve lipid quality in infant formulas.ClinicalTrials.gov Identifier NCT01611649 , retrospectively registered on May 25, 2012.
Project description:Anthropometric measurements, including height and length, are routinely needed for health research worldwide. Measurement boards are the current gold standard for obtaining the height and length of children. In community-based research, however, the size and weight of the measurement boards make them difficult and cumbersome to carry in the field. In addition, children and infants may express an unwillingness to be placed onto the measurement board. Electronic measuring tools commonly used in industry and contracting work are precise and portable. This study piloted a protocol to use an adapted laser measurement tool, the anthropometric measurement assist (AMA), to obtain height and recumbent length in children in Western Kenya. Intra- and inter-observer variability were determined and compared with measurement board measurements. Results of this initial pilot indicated that the AMA may be a viable alternative to measurement boards. The AMA can measure height/length accurately and reliably, is portable and is equivalent in price to measuring boards, making it a viable option for fieldwork in low-resourced countries.
Project description:BackgroundWe aimed to describe newborn body composition and identify which anthropometric ratio (weight/length; BMI; or ponderal index, PI) best predicts fat mass (FM) and fat-free mass (FFM).MethodsAir-displacement plethysmography (PEA POD) was used to estimate FM, FFM, and body fat percentage (BF%). Associations between FFM, FM, and BF% and weight/length, BMI, and PI were evaluated in 1,019 newborns using multivariate regression analysis. Charts for FM, FFM, and BF% were generated using a prescriptive subsample (n=247). Standards for the best-predicting anthropometric ratio were calculated utilizing the same population used for the INTERGROWTH-21st Newborn Size Standards (n=20,479).ResultsFFM and FM increased consistently during late pregnancy. Differential FM, BF%, and FFM patterns were observed for those born preterm (34+0-36+6 weeks' gestation) and with impaired intrauterine growth. Weight/length by gestational age (GA) was a better predictor of FFM and FM (adjusted R2=0.92 and 0.71, respectively) than BMI or PI, independent of sex, GA, and timing of measurement. Results were almost identical when only preterm newborns were studied. We present sex-specific centiles for weight/length ratio for GA.ConclusionsWeight/length best predicts newborn FFM and FM. There are differential FM, FFM, and BF% patterns by sex, GA, and size at birth.
Project description:BACKGROUND:Ultrasound scanning during the 2nd or the 3rd trimester of pregnancy for fetal size disturbances screening is heavily dependent of the choice of the reference chart. This study aimed to assess the agreement of Salomon and the Intergrowth 21st equations in evaluating fetal biometric measurements in a rural area of Burkina Faso, and to measure the effect of changing a reference chart. METHODS:Data collected in Nazoanga, Burkina Faso, between October 2010 and October 2012, during a clinical trial evaluating the safety and efficacy of several antimalarial treatments in pregnant women were analyzed. We included singleton pregnancies at 16-36?weeks gestation as determined by ultrasound measurements of fetal bi-parietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL). Expected mean and standard deviation at a given gestational age was computed using equations from Salomon references and using Intergrowth 21st standard. Then, z-scores were calculated and used subsequently to compare Salomon references with Intergrowth 21st standards. RESULTS:The analysis included 276 singleton pregnancies. Agreement was poor except for HC: mean difference?-?0.01, limits of agreement -?0.60 and 0.59. When AC was used as a surrogate of fetal size, switching from the reference of Salomon to the standards of Intergrowth 21st increased ten times the proportion of fetuses above the 90th percentile: 2.9 and 31.2%, respectively. Mean differences were larger in the third trimester than in the second trimester. However, agreement remained good for HC in both trimesters. Difference in the proportion of AC measurements above the 90th percentile using Salomon and Intergrowth 21st equations was greater in the second trimester (2.6 and 36.3%, respectively) than in the third trimester (3.5 and 19.8%, respectively). The greatest difference between the two charts was observed in the number of FL measurements classified as large in the second trimester (6.8 and 54.2%, using Salomon and Intergrowth 21st equations, respectively). CONCLUSION:The agreement between Intergrowth 21st and Salomon equations is poor apart from HC. This would imply different clinical decision regarding the management of the pregnancy.
Project description:BACKGROUND:Autopsy studies reveal that atherosclerosis lesions can be found as early as two years of age. To slow the development of this early pathology, obesity and dyslipidemia prevention should start from childhood making it urgent to explore new ways to evaluate dyslipidemia risk in children that can be applied widely, such as the non-invasive anthropometric evaluation. OBJECTIVE:Assess the metabolic profile of a pediatric population at a specific age to describe the association between anthropometric and biochemical cardiovascular disease risk factors; and evaluate selected anthropometric variables as potential predictors for dyslipidemic cardiovascular risk. DESIGN AND METHODS:Anthropometric features, bioimpedance parameters and fasting clinical profile were assessed in Lisbon and the Tagus Valley region pre-pubertal nine-year-old children (n = 1.496) from 2009-2013 in a descriptive, cross-sectional study. Anthropometric variables predictive power was evaluated through regression analysis. RESULTS:At least one abnormal lipid parameter was found in 65% of "normal weight", 73% of "overweight" and 81% of "obese" children according to the International Obesity Task Force (IOTF) standards. Dyslipidemia was present in 67.8% of children. Waist-hip ratio (WHR) explained 0.4% of total cholesterol (TC) variance. Waist circumference (WC) explained 2.8% of apolipoprotein (APO) A1 variance. Waist-circumference-to-height-ratio (WHtR) explained 2.7%, 2.8% and 1.9% of low-density lipoprotein cholesterol (LDL-c), APO B, and N_HDL-c variance, respectively. Children with abnormally high WHR levels had an increase in risk of 4.49, 3.40 and 5.30 times, respectively, for developing cardiovascular disease risk factors measured as high-risk levels of TC, LDL-c and non-HDL-c (N_HDL-c) (p<0.05). Only 29.9% of "normal weight" children had no anthropometric, bioimpedance or biochemical parameters associated with CV risk. CONCLUSION:A large proportion of school age children have at least one lipid profile abnormality. BMI, zBMI, calf circumference (CC), hip circumference (HC), WC, and WHR are directly associated with dyslipidemia, whereas HC and calf circumference (CC) adjusted to WC, and mid-upper arm circumference (MUAC), are all inversely associated with dyslipidemia. Selected anthropometric variables are likely to help predict increased odds of having CV risk factors.
Project description:INTRODUCTION:Children's well-being is highly influenced by their fetal growth. Adequate intrauterine growth (IUG) is a basic feature of a healthy pregnancy. The aim of our study was to assess IUG patterns in a rural and drought-affected population in the Rift Valley area of the Adami Tullu district in Oromia, Ethiopia. METHODS:We conducted a longitudinal, community-based study of IUG patterns utilizing serial ultrasound measurements. Data were collected for 17 months, from July 2016 to November 2017. We included 675 singleton foetuses ? 24 weeks old, based on ultrasound-derived estimates of gestational age, and followed them until delivery. We obtained head circumference, biparietal diameter, abdominal circumference, femur length, and estimated fetal weight at 26, 30, and 36 weeks. Fetal weight was estimated using the Hadlock algorithm, and the 5th, 10th, 25th, 50th, 75th, 90th, and 95th centiles were developed from this model. We compared the biometric measurements and fetal weight data from our study to the World Health Organization (WHO) and INTERGROWTH-21st fetal growth reference standards. RESULTS:Distribution of the biometric measurements and estimated fetal weights in our study were similar to those for the WHO and INTERGROWTH-21st references. Most measurements were between -2 and +2 of the reference z-scores. Based on the smoothed percentiles, the 5th, 50th, and 95th percentiles of our study had similar distribution patterns to the WHO chart, and the 50th percentile had a similar pattern to the INTERGROWTH-21st chart. CONCLUSIONS:Our study determined fetal growth patterns in a drought-affected rural community of Ethiopia using common ultrasound biometric measurements. We found similar IUG patterns to those indicated in the WHO and INTERGROWTH-21st fetal growth reference standards.
Project description:BACKGROUND:Perinatal and newborn complications are major risk factors for unfavorable fetal and neonatal outcomes. Gestational dating and growth monitoring can be instrumental in the identification and management of high-risk pregnancies and births. The INTERGROWTH-21st Project developed the first global standards for gestational dating and fetal and newborn growth monitoring, supplying a toolkit for clinicians. This study aimed to assess the feasibility and acceptability of the first known implementation study of these standards in a low resource setting. METHODS:The study was performed in two 12-month phases from March 2016 to March 2018 at Jacaranda Health, a private maternity hospital in peri-urban Nairobi, Kenya. In-depth interviews, focus group discussions and a provider survey were utilized to evaluate providers' experiences during implementation. Client chart data, for pregnant women attending antenatal care and/or delivering at Jacaranda Health along with their newborns, were captured to assess uptake and effect of the standards on clinical decision-making. RESULTS:Facility-level support and provider buy-in proved to be critical factors driving the success of implementing the standards. However, additional support was needed to strengthen capacity to conduct and interpret ultrasounds and maintain motivation among providers. We observed a significant increase in the uptake of obstetric ultrasounds, particularly gestational dating, during the implementation of the standards. Although no significant changes were detected in the identification of high-risk pregnancies, referrals and deliveries by Cesarean section during implementation, we did observe a significant reduction in inductions for post-date. No significant barriers were reported regarding the use of the newborn standards. Over 80% of providers advocated for the standards to remain in place with some enhancements related mainly to training, advocacy and procurement. CONCLUSIONS:The findings are timely with increasing global adoption of the standards and the challenging and multi-faceted nature of translating new, evidence-based guidelines into routine clinical practice.
Project description:OBJECTIVES:To describe the construction of the international INTERGROWTH-21st Neurodevelopment Assessment (INTER-NDA) standards for child development at 2 years by reporting the cognitive, language, motor and behaviour outcomes in optimally healthy and nourished children in the INTERGROWTH-21st Project. DESIGN:Population-based cohort study, the INTERGROWTH-21st Project. SETTING:Brazil, India, Italy, Kenya and the UK. PARTICIPANTS:1181 children prospectively recruited from early fetal life according to the prescriptive WHO approach, and confirmed to be at low risk of adverse perinatal and postnatal outcomes. PRIMARY MEASURES:Scaled INTER-NDA domain scores for cognition, language, fine and gross motor skills and behaviour; vision outcomes measured on the Cardiff tests; attentional problems and emotional reactivity measured on the respective subscales of the preschool Child Behaviour Checklist; and the age of acquisition of the WHO gross motor milestones. RESULTS:Scaled INTER-NDA domain scores are presented as centiles, which were constructed according to the prescriptive WHO approach and excluded children born preterm and those with significant postnatal/neurological morbidity. For all domains, except negative behaviour, higher scores reflect better outcomes and the threshold for normality was defined as ?10th centile. For the INTER-NDA's cognitive, fine motor, gross motor, language and positive behaviour domains these are ?38.5, ?25.7, ?51.7, ?17.8 and ?51.4, respectively. The threshold for normality for the INTER-NDA's negative behaviour domain is ?50.0, that is, ?90th centile. At 22-30 months of age, the cohort overlapped with the WHO motor milestone centiles, showed low postnatal morbidity (<10%), and vision outcomes, attentional problems and emotional reactivity scores within the respective normative ranges. CONCLUSIONS:From this large, healthy and well-nourished, international cohort, we have constructed, using the WHO prescriptive methodology, international INTER-NDA standards for child development at 2 years of age. Standards, rather than references, are recommended for population-level screening and the identification of children at risk of adverse outcomes.
Project description:Three recently completed longitudinal cohort studies have developed intrauterine fetal growth charts, one in the United States and two international. This expert review compares and contrasts the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies, INTERGROWTH-21st and World Health Organization Multicentre Growth Reference Study conclusions in light of differences in aims, sampling frames, and analytical approaches. An area of controversy is whether a single growth reference is representative of growth, regardless of ethnic or country origin. The INTERGROWTH and World Health Organization Fetal studies used a similar approach as the World Health Organization Multicentre Growth Reference Study for infants and children, the aim of which was to create a single international reference for the best physiological growth for children aged 0-5 years. INTERGROWTH made the same assumption (ie, that there would be no differences internationally among countries or racial/ethnic groups in fetal growth when conditions were optimal). INTERGROWTH found differences in crown-rump length and head circumference among countries but interpreted the differences as not meaningful and presented a pooled standard. The World Health Organization Multicentre Growth Reference Study was designed to create a pooled reference, although they evaluated for and presented country differences, along with discussion of the implications. The Eunice Kennedy Shriver National Institute of Child Health and Human Development Study was designed to assess whether racial/ethnic-specific fetal growth standards were needed, in recognition of the fact that fetal size is commonly estimated from dimensions (head circumference, abdominal circumference, and femur length) in which there are known differences in children and adults of differing racial/ethnic groups. A pooled standard would be derived if no racial/ethnic differences were found. Highly statistically significant racial/ethnic differences in fetal growth were found resulting in the publication of racial/ethnic-specific derived standards. Despite all 3 studies including low-risk status women, the percentiles for fetal dimensions and estimated fetal weight varied among the studies. Specifically, at 39 weeks, the 50th percentile for estimated fetal weight was 3502 g for whites, 3330 g for Hispanics, 3263 g for Asians, and 3256 for blacks in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Study, compared with 3186 g for INTERGROWTH and 3403 g for World Health Organization Multicentre Growth Reference Study. When applying these standards to a clinical population, it is important to be aware that different percentages of small- and large-for-gestational-age fetuses will be identified. Also, it may be necessary to use more restrictive cut points, such as the 2.5th or 97.5th, for small-for-gestational-age or large-for-gestational-age fetuses, respectively. Ideally, a comparison of diagnostic accuracy, or misclassification rates, of small-for-gestational-age and large-for-gestational-age fetuses in relation to morbidity and mortality using different criteria is necessary to make recommendations and remains an important data gap. Identification of the appropriate percentile cutoffs in relation to neonatal morbidity and mortality is needed in local populations, depending on which fetal growth chart is used. On a final point, assessment of fetal growth with a one-time measurement remains standard clinical practice, despite recognition that a single measurement can indicate only size. Ultimately, it is knowledge about fetal growth in addition to other factors and clinical judgment that should trigger intervention.