Estimation of body weight in children in the absence of scales: a necessary measurement to insure accurate drug dosing

Weight estimation in two groups of Ghanaian children with chronic diseases using Broselow, Mercy, PAWPER XL and PAWPER XL-MAC tapes

Introduction

The performance of various weight estimation methods in children with sickle cell disease (SCD) and heart disease (HD) has not been studied. We aimed to determine and compare the accuracies of the Broselow, Mercy, PAWPER XL and PAWPER XL-MAC tapes in Ghanaian children with no known chronic diseases (controls), SCD and HD.

Methods

We prospectively recruited 631 children (199 with HD, 209 SCD and 223 controls) from the Komfo Anokye Teaching Hospital (KATH). Their weights were estimated using the Broselow, Mercy, PAWPER XL and PAWPER XL-MAC tapes. These estimated weights were compared to measured weight using mean percentage error (MPE), the proportion of weight estimates within ±10% (P10) and ±20% (P20) of measured weight. Bland-Altman limits of agreement (LOA) were determined to assess the precision of weight estimation and agreement with measured weight.

Results

The PAWPER XL, Mercy and PAWPER XL-MAC were the most accurate in all groups of children studied. All methods except the Broselow tape (BT), which performed best in the control group, had their best performance among children with SCD with negligible critical error rates (proportion of children with weight estimates > 20% of their actual weight). The P20 in the various groups of children using the BT were 88.36%, 80.21% and 51.10% respectively in the control, SCD and HD groups. The Mercy, PAWPER XL and PAWPER XL MAC tapes were generally above 90% in all groups.

Discussion

The Mercy, PAWPER XL and PAWPER XL-MAC tapes performed significantly better than the BT in all groups of children studied. These methods of weight estimation performed best in children with SCD with very little critical error.

Design and validation of equations for weight estimation in adolescents

INTRODUCTION

Measuring weight is difficult to be carried out in bedridden people, with physical deformity or in emergency units. Under these circumstances, one option is to estimate the weight.

OBJECTIVES

The aim of this study is to propose and validate equations for estimating the weight of Brazilian adolescents based on anthropometric variables related to body weight.

METHODS

The study was developed based on a database created from data collection of a primary project, which had information from 662 Brazilian adolescents (10 to 19 years old). Based on the variables sex, age (days), weight (kg), height (m) and neck circumference (NC) (cm), equations for estimating weight of adolescents were proposed. The formulas were proposed after performing multiple linear regression models and subsequently tested and validated using appropriate statistical tests, considering 99% confidence.

RESULTS

Two formulas were generated, the "Rucco Formulas-Adolescents", one for girls: -131.63091 + (0.00209 × A) + (37.57813 × H) + (3.71482 x NC) and another for boys: - 15.2854 + (-0.00414 × A)+ (14.30315 × H2)+ (0.04888 x NC2). Statistical test (R2) indicated that the proposed formulas are suitable for estimating weight. Low values of REQM and high values of CCI (> 0.8) also reinforce the quality of the proposed formulas.

CONCLUSIONS

The current weight of adolescents can be estimated with adequate accuracy and precision using sex-specific "Rucco Formulas-Adolescents", generated from regression models using only three predictor variables.

A new method to estimate children's weight accurately in emergency settings using foot length and mid-upper arm circumference

BACKGROUND

In emergency settings, medication dosages are primarily determined based on the child's weight; however, the healthcare personnel sometimes may have to make the first intervention without knowing the patient's weight, which may result in an underdose or overdose of the medication. We aimed to find a reliable method to estimate children's bodyweight, including the obese and malnourished.

METHODS

We conducted the study with children between the ages of 3 and 17 years. We measured the children's bodyweight, right foot length, and mid-upper arm circumference in centimeters during their examination. We created a concise formula through regression analysis to estimate the patients' weight based on the right foot length and mid-upper arm circumference. Finally, we compared this formula to other conventional formulae.

RESULTS

The study included 741 patients whose average age was 8.4±3.9 (3-17) years. A high correlation was found between the patients' foot length, arm circumference, and bodyweight (R: 0.866, p<0.001 and R: 0.910, p<0.001, respectively). A single formula was created by regression analysis based on foot length and the mid-upper arm circumference without including sex and age in the calculation to make a more straightforward and faster calculation in emergency cases.

CONCLUSION

The formula created may be advantageous for reliably and easily estimating the weight of children aged 3-17 of any sex and body habitus in emergency settings without special equipment. This newly developed formula may enable a low-cost optimal level of weight estimation without the need for special equipment.

Accuracy of Weight Estimation in Children Using the Broselow, PAWPER XL, PAWPER XL-MAC, and Mercy Tapes

OBJECTIVES

Quick and accurate estimate of a child's weight is often required for medical interventions like drug dose calculation when scale measured weights cannot be obtained safely. Length-based methods of weight estimation are more accurate than age-based methods, with the most accurate being the length-based, habitus-modified methods. This study sought to determine and compare the accuracies of the 2017 Broselow tape, Paediatric Advanced Weight Prediction in the Emergency Room Extra-Long (PAWPER XL) tape, Paediatric Advanced Weight Prediction in the Emergency Room Extra-Long Mid-Arm Circumference (PAWPER XL-MAC) tape, and the 2-dimensional (2D) Mercy tape in Ghanaian children.

METHODS

A cross-sectional study was conducted at the Tamale Teaching Hospital in Ghana. Eight hundred forty children between 2 months and 13 years had their weights estimated by the 2017 Broselow, PAWPER XL, PAWPER XL-MAC, and 2D Mercy tapes. Accuracy of the methods was determined by percentage of weight estimated to within 10% and 20% of actual weight. Mean percentage error and the Bland-Altman analysis were used to assess bias and precision.

RESULTS

The proportion of weight estimates within 10% and 20% of actual weight for Broselow tape were 47.5% and 82.3%, for 2D Mercy tape were 73.1% and 96.3%, for PAWPER XL-MAC were 77.6% and 97.5%, and for PAWPER XL were 81.7% and 96.8%, respectively. The Broselow tape had the greatest bias and least precision among the 4 methods. The Mercy, PAWPER XL-MAC, and PAWPER XL tapes had similar performance, but all performed significantly better than the Broselow tape in pairwise comparison. The best weight estimation method overall was the PAWPER XL tape as it also had the least bias and greatest precision.

CONCLUSIONS

The Mercy, PAWPER XL-MAC, and PAWPER XL tapes were more accurate than the 2017 Broselow tape and should be used in preference in Ghana and countries with similar population structure.

Development of equations and software for estimating weight in children with cerebral palsy

AIM

To develop equations and software to estimate weight using segmental measures for children with cerebral palsy (CP).

METHOD

This was a cross-sectional study. Children and adolescents with CP of both sexes from 2 to 19 years old from five cities in Argentina were included. Weight, mid-upper arm circumference (MUAC), and clinical covariables were collected. Linear regression models with weight as the dependent variable and body segment lengths as predictors were developed and compared for R² , adjusted R² , and the root mean square of the error.

RESULTS

In total, 381 children and adolescents (mean age 10y 5mo [SD 4y 9mo], range 2-19y; 231 males, 150 females) with a confirmed diagnosis of CP were included. Gross motor function based on the Gross Motor Function Classification System (GMFCS) was as follows: level I, 59; II, 55; III, 59; IV, 69; V, 139. The interaction between weight and other variables such as MUAC, sex, GMFCS, and age was analysed. The concordance correlation coefficient between estimated and observed weight was 0.94 (95% CI 0.93-0.95). From the results of the equations, a free software tool, named Weight Calculator CP, was developed.

INTERPRETATION

Weight in children with CP can be predicted using MUAC, GMFCS, and age. Weight Calculator CP can be used in clinical practice when direct weight cannot be obtained. What this paper adds Equations can be used to estimate weight in children with cerebral palsy via body segments. Weight can be estimated according to age and gross motor function. The average difference between estimated and observed weights was 119g.

Comparison of paediatric weight estimation methods at a tertiary hospital in Ghana

Introduction

Weight estimation in children is critical in paediatric emergencies. The Broselow Tape (BT) and most age-based formulae for weight estimation were derived in high-income countries and are thought to overestimate the weight of children in low-income countries. This study sought to validate the 2017 BT, and eight age-based weight estimation formulae among Ghanaian children and to derive a weight estimation formula using this data.

Methods

A cross-sectional study was conducted in the Tamale Teaching Hospital (TTH) in Ghana. Children aged between 2 months and 13 years had their weights estimated by the 2017 BT and eight age-based formulae. These estimated weights were compared to the weight of the children measured by a calibrated Seca scale using mean percentage error (MPE) and the percentage of weight estimates within 10% and 20% of actual weight. Bland-Altman method was used to assess agreement between estimated and actual weight of the children. A new formula was derived by linear regression.

Results

Seven hundred and seventy-five children took part in the study. The 2017 BT, Original APLS (APLS1) and Nelson's formulae performed best with proportion of weight estimates within 10% of actual weight being 47.5%, 51.1% and 47.5% respectively. The formula developed in this study was: W_E = 3Am / 10 + 5 (for infants <12 months), W_E = 2A + 7 (1 to 4 years) and W_E = 2A + 9 (5 to 13 years), where W_E is estimated weight, A_m is age in completed months and A is age in completed years. The new formula had similar accuracy as the three best performing methods in this study.

Conclusion

The Broselow Tape, APLS1 and the Nelson's formula were the most accurate in this study. APLS1 and the Broselow Tape can be used for weight estimation in Ghanaian children when no other better method is available.

Desarrollo de ecuaciones y software para la estimación de peso en niños y niñas con parálisis cerebral

Objetivo

Desarrollar ecuaciones y software para estimar peso usando medidas de segmentos corporales en niños con parálisis cerebral (PC).

Método

Este fue un estudio transversal. Se incluyeron niños y adolescentes con PC de ambos sexos de 2 a 19 años de cinco ciudades de Argentina. Se recolectó el peso, la circunferencia media del brazo (CMB) y covariables clínicas. Se desarrollaron modelos de regresión lineal con el peso como variable dependiente y las medidas de los segmentos corporales como predictores, y se compararon paraR2,R2ajustado y la raíz cuadrada media del error.

Resultados

En total, se incluyeron 381 niños y adolescentes con diagnóstico confirmado de PC (edad media 10 años y 5 meses [DE 4 años 9 meses], rango de 2 a 19 años; 231 hombres, 150 mujeres). La función motora gruesa basada en el Sistema de clasificación de función motora gruesa (GMFCS) fue la siguiente: nivel I, 59; II, 55; III, 59; IV, 69; V, 139. Se analizó la interacción entre el peso y otras variables como CMB, sexo, GMFCS y edad. El coeficiente de correlación de concordancia entre el peso estimado y el observado fue de 0,94 (IC 95%: 0,93–0,95). A partir de los resultados de las ecuaciones, se desarrolló una herramienta de software gratuita, denominada Calculador de Peso PC.

Interpretación

El peso de los niños con parálisis cerebral se puede predecir utilizando CMB, GMFCS y edad. Calculador de Peso PC se puede utilizar en la práctica clínica cuando no se puede obtener el peso directo.

Lo que agrega este artículo

A validation of the PAWPER XL-MAC tape for total body weight estimation in preschool children from low- and middle-income countries

Importance

The PAWPER tape system is one of the three most accurate paediatric weight estimation systems in the world. The latest version of the tape, which does not rely on a subjective assessment of habitus, is the PAWPER XL-MAC method which uses length and mid-arm circumference (MAC) to estimate weight. It was derived and validated in a population in the USA and has not yet been fully validated in a population from a resource-limited setting.

Objective

The objective of this study was to evaluate the performance of the PAWPER XL-MAC tape weight estimation system in a large dataset sample of children from resource-limited settings.

Methods

This was a “virtual” study in which weight estimates were generated using the PAWPER XL-MAC tape and Broselow tape 2007B and 2011A editions in a very large open access dataset. The dataset contained anthropometric information of children aged 6 to 59 months from standardised nutritional surveys in 51 low- and middle-income countries. The performance of PAWPER XL-MAC method was compared with the Broselow tape and a new length- and habitus-based tape, the Ralston method.

Main outcomes and measures

The bias of the weight estimation methods was assessed using the mean percentage error (MPE) and precision using the 95% limits of agreement (LOA) of the MPE. The overall accuracy was denoted by the percentage of weight estimates falling within 10% and 20% of actual weight (abbreviated as p10 and p20 respectively).

Results

The MPE (LOA) for the PAWPER XL-MAC tape, the Broselow 2007B and 2011A and Ralston method were 1.9 (-15.3, 19.2), 5.4 (-15.9, 26.7), 7.7 (-13.3, 30.5) and -0.7 (-20.2, 19.3) respectively. The p10 and p20 for each method were 79.3% and 96.9% for the PAWPER XL-MAC tape, 64.3% and 91.0% for the Broselow tape 2007B, 55.5% and 85.9% for the Broselow tape 2011A and 67.4 and 94.0% for the Ralston method respectively. The PAWPER XL-MAC system was statistically significantly more accurate than the Broselow tape 2011A, the Broselow tape 2007B and the Ralston method. The relative difference in accuracy (p10) was 43% (odds ratio 4.4 (4.4, 4.5), p<0.001), 23% (odds ratio 2.9 (2.8, 2.9), p<0.001) and 18% (odds ratio 1.8 (1.8, 1.8), p<0.001) compared to each method, respectively.

Conclusions and relevance

The PAWPER XL-MAC tape performed well in this study and was statistically significantly more accurate than both the Broselow tape editions and the Ralston method. This difference was substantial and clinically important. The tape did not perform as well at extremes of habitus-type, however, and might benefit from recalibration.

The accuracy of the Broselow tape as a weight estimation tool and a drug-dosing guide - A systematic review and meta-analysis

AIMS

The Broselow tape is widely used as a weight-estimation device and drug-dosing guide aid, but concerns about its accuracy and its efficacy have emerged in the last decade. The aim of this study was to systematically review the literature to analyse the accuracy of the Broselow tape as a weight estimation device and review evidence of its utility as a drug-dosing guide.

METHODS

This was a MOOSE-driven systematic review and meta-analysis, which focused on studies evaluating the accuracy of the Broselow tape and studies reviewing its use as a drug-dosing aid.

MAIN RESULTS

The tape has undergone substantial changes over the years, but there was no evidence to show that the changes have improved weight-estimation performance. The weight-estimation accuracy of the tape was suboptimal in all populations, with just over 50% of children receiving an estimation within 10% of their actual weight. The overestimation of weight in low- and middle-income countries was often extreme. This indicated a significant potential for potentially harmful medication errors. The limited available evidence on the value of the tape as a drug-dosing guide indicated that the tape was frequently used incorrectly and contained insufficient information to function without additional resources.

CONCLUSIONS

The Broselow tape lacked sufficient accuracy as a weight estimation and drug-dosing tool when compared to other available techniques. In addition, the Broselow tape contains insufficient drug-dosing information to function as a complete resuscitation aid without additional material. The frequent rate of incorrect usage of the tape indicated that appropriate training with the tape is mandatory to reduce errors.

A systematic review and meta-analysis of the accuracy of weight estimation systems used in paediatric emergency care in developing countries

Introduction

When weight cannot be measured during the management of medical emergencies in children, a convenient, quick and accurate method of weight estimation is required, as many drug doses and other interventions are based on body weight. Many weight estimation methodologies in current use have been shown to be inaccurate, especially in low- and middle-income countries with a high prevalence of underweight children. This meta-analysis evaluated the accuracy of weight estimation systems in children from studies from low- and middle-income countries.

Methods

Articles from low- and middle-income countries were screened for inclusion to evaluate and compare the accuracy of existing systems and the newer dual length- and habitus-based methods, using standard meta-analysis techniques.

Results

The 2D systems and parental estimates performed best overall. The PAWPER tape, parental estimates, the Wozniak method and the Mercy method were the most accurate systems with percentage of weight estimates within 10% of actual weight (PW10) accuracies of 86.9%, 80.4%, 72.1% and 71.4% respectively. The Broselow tape (PW10 47.1%) achieved a moderate accuracy and age-based estimates a very low accuracy (PW10 11.8–47.5%).

Conclusions

The PAWPER tape, the Wozniak method and the Mercy method achieved an acceptable level of accuracy in studies from low- and middle-income countries and should preferentially be used and further advanced for clinical emergency medicine practice. Parental estimates may be considered if the regular caregiver of the child is present and a recent measured weight is known. The Broselow tape and age-based formulas should be abandoned in low- and middle-income country populations as they are potentially dangerously inaccurate.

The accuracy of emergency weight estimation systems in children-a systematic review and meta-analysis

The safe and effective administration of fluids and medications during the management of medical emergencies in children depends on an appropriately determined dose, based on body weight. Weight can often not be measured in these circumstances and a convenient, quick and accurate method of weight estimation is required. Most methods in current use are not accurate enough, but the newer length-based, habitus-modified (two-dimensional) systems have shown significantly higher accuracy. This meta-analysis evaluated the accuracy of weight estimation systems in children. Articles were screened for inclusion into two study arms: to determine an appropriate accuracy target for weight estimation systems; and to evaluate the accuracy of existing systems using standard meta-analysis techniques. There was no evidence found to support any specific goal of accuracy. Based on the findings of this study, a proposed minimum accuracy of 70% of estimations within 10% of actual weight (PW10 > 70%), and 95% within 20% of actual weight (PW20 > 95%) should be demonstrated by a weight estimation system before being considered to be accurate. In the meta-analysis, the two-dimensional systems performed best. The Mercy method (PW10 70.9%, PW20 95.3%), the PAWPER tape (PW10 78.0%, PW20 96.6%) and parental estimates (PW10 69.8%, PW20 87.1%) were the most accurate systems investigated, with the Broselow tape (PW10 55.6%, PW20 81.2%) achieving a lesser accuracy. Age-based estimates achieved a very low accuracy. Age- and length-based systems had a substantial difference in over- and underestimation of weight in high-income and low- and middle-income populations. A benchmark for minimum accuracy is recommended for weight estimation studies and a PW10 > 70% with PW20 > 95% is suggested. The Mercy method, the PAWPER tape and parental estimates were the most accurate weight estimation systems followed by length-based and age-based systems. The use of age-based formulas should be abandoned because of their poor accuracy.

A Comparative Study on the Results of Estimating Children's Weights Based on Arm Circumference, Height, and Body Habitus against Estimated Weight Broselow on 2-24 Months Children in Isfahan

Background:

Resuscitation of children in different treatment wards is a challenge. Given that the pediatric drug dosing is based on weight and weighing is not practical in emergency situations, it is critical to employ a fast, easy, and reliable technique. Hence, this study attempted to evaluate the real weight children against Broselow estimation.

Materials and Methods:

This cross-sectional study involved 1500 children of 2–24 months referred to Isfahan urban and rural health centers in 2015. Children's estimated weights were measured based on the standard Broselow tape and real weights through a digital scale. The factors such as age, sex, height, arm circumference, head circumference, and living place of children were recorded. The collected data were analyzed through independent t-test, ANOVA, and linear regression using SPSS (version 20).

Results:

The weight difference of children through Broselow estimation was 0.019 kg, and the correlation coefficient was 0.893 (P > 0.05). The difference sorted by age ranges was significant only in >12 months (P < 0.05). It was estimated at error of 10% to be 68.9% correctly. The mean weight estimation error was significant sorted by weight, sex, habitus, and living place of children (P < 0.001).

Conclusion:

Although Broselow tape has been proved to be accurate it led to a significant error at different age ranges. Hence, the present study estimated the age, arm circumference, and height of Iranian children based on new formulas providing more successful tool through controlling the confounding factors in estimating the real weight.

Estimating the weight of ethnically diverse children attending an Australian emergency department: a prospective, blinded, comparison of age-based and length-based tools including Mercy, PAWPER and Broselow

OBJECTIVE

To prospectively compare the actual weights of Australian children in an ethnically diverse metropolitan setting with the predicted weights using the Paediatric Advanced Weight Prediction in the Emergency Room (PAWPER) tape, Broselow tape, Mercy system and calculated weights using the updated Advanced Paediatric Life Support (APLS), Luscombe and Owens and Best Guess formulae.

METHODS

A prospective, cross-sectional, observational, blinded, convenience study conducted at the Children's Hospital at Westmead Paediatric Emergency Department in Sydney, Australia. Comparisons were made using Bland-Altman plots, mean difference, limits of agreement and estimated weight within 10% and 20% of actual weight.

RESULTS

199 patients were enrolled in the study with a mean actual weight of 27.2 kg (SD 17.2). Length-based tools, with or without body habitus adjustment, performed better than age-based formulae. When measuring estimated weight within 10% of actual weight, PAWPER performed best with 73%, followed by Mercy (69%), PAWPER with no adjustment (62%), Broselow (60%), Best Guess (47%), Luscombe and Owens (41%) and revised APLS (40%). Mean difference was similar across all methods ranging from 0.4 kg (0.0, 0.9) for Mercy to -2.2 kg (-3.5, -0.9) for revised APLS. Limits of agreement were narrower for the length-based tools (-5.9, 6.8 Mercy; -8.3, 5.6 Broselow; -9.0, 7.1 PAWPER adjusted; -12.1, 9.2 PAWPER unadjusted) than the age-based formulae (-18.6, 17.4 Best Guess; -19.4, 15.1 revised APLS, -21.8, 17.7 Luscombe and Owens).

CONCLUSION

In an ethnically diverse population, length-based methods with or without body habitus modification are superior to age-based methods for predicting actual body weight. Body habitus modifications increase the accuracy and precision slightly.

Mid-arm circumference can be used to estimate weight of adult and adolescent patients

Objectives

Many drug and fluid regimens in emergency medicine are weight dependent in adults, but no standard adult weight estimation tools exist. Paediatric weight is often estimated in emergency situations using methods based on age or height when direct measurement is not possible, and recently, methods based on mid-arm circumference (MAC) have also been developed. The aim of this study was to derive and validate an accurate MAC-based method for weight estimation for use in all age groups.

Methods

Data were obtained from the US National Health and Nutrition Examination Survey (NHANES). MAC-based methods of weight estimation were derived in 8498 subjects (5595 adults aged 16–80 years, 2903 children aged 1–15.9 years) from the NHANES 2011–2012 dataset, using linear regression. NHANES 2009–2010 was used for validation in 9022 subjects (6049 adults aged 16–79 years, 2973 children aged 1–15.9 years).

Results

A simplified method of MAC-based weight estimation was derived from linear regression equation: weight in kg=4×MAC (in cm)—50. On validation, results in children aged 1–10.9 years were poor. In adults and children aged 11–15.9 years, over 60%, 90% and 98% of estimates fell, respectively, within 10%, 20% and 30% of actual weights when using the simplified formula.

Conclusions

In this description of a method for estimating weight in adults, we have derived and validated a simplified formula that is at least as precise in adults and adolescents as commonly used paediatric weight estimation tools in children.

Weight Estimation Tool for Children Aged 6 to 59 Months in Limited-Resource Settings

Importance

A simple, reliable anthropometric tool for rapid estimation of weight in children would be useful in limited-resource settings where current weight estimation tools are not uniformly reliable, nearly all global under-five mortality occurs, severe acute malnutrition is a significant contributor in approximately one-third of under-five mortality, and a weight scale may not be immediately available in emergencies to first-response providers.

Objective

To determine the accuracy and precision of mid-upper arm circumference (MUAC) and height as weight estimation tools in children under five years of age in low-to-middle income countries.

Design

This was a retrospective observational study. Data were collected in 560 nutritional surveys during 1992–2006 using a modified Expanded Program of Immunization two-stage cluster sample design.

Setting

Locations with high prevalence of acute and chronic malnutrition.

Participants

A total of 453,990 children met inclusion criteria (age 6–59 months; weight ≤ 25 kg; MUAC 80–200 mm) and exclusion criteria (bilateral pitting edema; biologically implausible weight-for-height z-score (WHZ), weight-for-age z-score (WAZ), and height-for-age z-score (HAZ) values).

Exposures

Weight was estimated using Broselow Tape, Hong Kong formula, and database MUAC alone, height alone, and height and MUAC combined.

Main Outcomes and Measures

Mean percentage difference between true and estimated weight, proportion of estimates accurate to within ± 25% and ± 10% of true weight, weighted Kappa statistic, and Bland-Altman bias were reported as measures of tool accuracy. Standard deviation of mean percentage difference and Bland-Altman 95% limits of agreement were reported as measures of tool precision.

Results

Database height was a more accurate and precise predictor of weight compared to Broselow Tape 2007 [B], Broselow Tape 2011 [A], and MUAC. Mean percentage difference between true and estimated weight was +0.49% (SD = 10.33%); proportion of estimates accurate to within ± 25% of true weight was 97.36% (95% CI 97.40%, 97.46%); and Bland-Altman bias and 95% limits of agreement were 0.05 kg and (-2.15 kg; 2.24 kg). The height model fitted for MUAC classes was accurate and precise. For MUAC < 115 mm, the proportion of estimates accurate to within ± 25% of true weight was 97.15% (95% CI 96.90%, 97.42%) and the Bland-Altman bias and 95% limits of agreement were 0.08 kg and (-1.21 kg; 1.37 kg). For MUAC between 115 and 125 mm, the proportion of estimates accurate to within ± 25% of true weight was 98.93% (95% CI 98.82%, 99.03%) and Bland-Altman bias and 95% limits of agreement were 0.05 kg and (-1.15 kg; 1.24 kg). For MUAC > 125 mm, the proportion of estimates accurate to within ± 25% of true weight was 98.33% (95% CI 98.29%, 98.37%) and Bland-Altman bias and 95% limits of agreement were 0.05 kg and (-2.08 kg; 2.19 kg).

Conclusions and Relevance

Models estimating weight from height alone and height with MUAC class in children aged 6–59 months in a database from low-to-middle income countries were more accurate and precise than previous weight estimation tools. A height-based weight estimation tape stratified according to MUAC classes is proposed for children aged 6–59 months in limited-resource settings.

Emergency weight estimation lookup tables for New Zealand children aged 5-10 years

OBJECTIVE

To derive novel emergency weight estimation tables for New Zealand children aged 5-10 years using ethnicity and sex to increase accuracy and precision.

METHODS

Using an existing dataset (collected in five New Zealand primary schools during July 2013; n = 376), body mass index and current emergency weight estimates were calculated. Stepwise regression with Akanke Information produced two best-fit models for predicting weight, one based on age and the other on height. Potential explanatory variables included ethnicity, sex and body habitus.

RESULTS

The length-based model included height, ethnicity and body habitus. Accuracy (weight estimates within 10% of actual weight) for the length-based lookup table (74.8%) was similar to that for the Broselow-Luten tape (73.4%). The age-based model included age, sex, ethnicity and body habitus. Accuracy (51.3%) for the age-based lookup table was better than for existing formulae including Shann (45.7%), Advanced Paediatric Life Support (39.1%) and Theron (28.7%).

CONCLUSION

The most accurate method for weight estimation in Auckland children aged 5-10 years is either the novel length-based lookup table or the existing Broselow-Luten tape. When length-based methods are not possible, the age-based lookup tables incorporating age, sex, ethnicity and body habitus are more accurate than existing methods of weight estimation.

The Broselow and Handtevy Resuscitation Tapes: A Comparison of the Performance of Pediatric Weight Prediction

OBJECTIVES

To assess the performance of two pediatric length-based tapes (Broselow and Handtevy) in predicting actual weights of US children.

METHODS

In this descriptive study, weights and lengths of children (newborn through 13 years of age) were extracted from the 2009-2010 National Health and Nutrition Examination Survey (NHANES). Using the measured length ranges for each tape and the NHANES-extracted length data, every case from the study sample was coded into Broselow and Handtevy zones. Mean weights were calculated for each zone and compared to the predicted Broselow and Handtevy weights using measures of bias, precision, and accuracy. A sub-sample was examined that excluded cases with body mass index (BMI)≥95th percentile. Weights of children longer than each tape also were examined.

RESULTS

A total of 3,018 cases from the NHANES database met criteria. Although both tapes underestimated children's weight, the Broselow tape outperformed the Handtevy tape across most length ranges in measures of bias, precision, and accuracy of predicted weights relative to actual weights. Accuracy was higher in the Broselow tape for shorter children and in the Handtevy tape for taller children. Among the sub-sample with cases of BMI≥95th percentile removed, performance of the Handtevy tape improved, yet the Broselow tape still performed better. When assessing the weights of children who were longer than either tape, the actual mean weights did not approximate adult weights; although, those exceeding the Handtevy tape were closer.

CONCLUSIONS

For pediatric weight estimation, the Broselow tape performed better overall than the Handtevy tape and more closely approximated actual weight. Lowe CG , Campwala RT , Ziv N , Wang VJ . The Broselow and Handtevy resuscitation tapes: a comparison of the performance of pediatric weight prediction. Prehosp Disaster Med. 2016;31(4):364-375.

Estimating Weight in Children With Down Syndrome

Objective. Significant attention has been paid to weight estimation in settings where scales are impractical or unavailable; however, no studies have evaluated the performance of published weight estimation methods in children with Down syndrome. This study was designed to evaluate the predictive performance of various methods in this population with well-established differences in height and weight for age. Methods. This was a prospective study of children aged 0 to 18 years with Down syndrome. Anthropometric measurements including height, weight, humeral length, and mid-upper arm circumference were collected and applied to 4 distinct weight estimation strategies based on age (APLS), length (Broselow), habitus (Cattermole), and length plus habitus (Mercy). Predictive performance was evaluated by examining residual error (RE), percentage error (PE), root mean square error (RMSE), limits of agreement, and intraclass correlation coefficients. Results. A total of 318 children distributed across age, gender, and body mass index percentile were enrolled. APLS and Mercy showed the smallest degree of bias (PE = 7.8 ± 24.5% and −3.9 ± 12.4%, respectively). Broselow suffered the most extreme underestimation (−63%), whereas the APLS suffered the greatest degree of overestimation (107%). Mercy demonstrated the highest intraclass correlation coefficient (0.987 vs 0.867-0.885) and predicted weight within 20% of actual in the largest proportion of participants (88% vs 40% to 76%). All methods were less robust in children with Down syndrome than reported for unaffected children. Conclusions. Mercy offered the best option for weight estimation in children with Down syndrome. Additional anthropometric data collected in this special population would allow investigators to refine existing weight estimation strategies specifically for these children.

The challenge of obesity in paediatric leukaemia treatment: it is not just size that matters

In the last two decades, tremendous advances have been made in the treatment of acute lymphocytic leukaemia (ALL) in children with 5 year 'cure' rates in excess of 90%. The maintenance of remission is due, in part, to individualisation of therapy which must consider age, body size, genetic constitution and the impact of disease on drug disposition and action. This review, focused on treatment of ALL and one of the therapeutic mainstays, 6-mercaptopurine, illustrates the importance of obesity as a modulating factor in dose individualisation.