Evaluation of the Mercy TAPE: performance against the standard for pediatric weight estimation

Comparing the performance of pediatric weight estimation methods

BACKGROUND

Weight estimation is essential in the care of ill children when a weight cannot be obtained. This is particularly important for children with medical complexity, who are at higher risk for adverse drug events. Our objective was to compare the accuracy of different methods of weight estimation in children and stratify by the presence of medical complexity.

METHODS

We performed a retrospective cross-sectional study of children (<18 years) seen in the emergency department (ED) or ambulatory clinic from January 1, 2013 to December 31, 2022 at a tertiary academic pediatric center. We compared the performance of nine age-based formulae and two length-based methods using metrics of mean average error (MAE), root mean square error (RMSE), and agreement within 10% and 20% of measured weight. We additionally evaluated the approaches stratified by body mass index (BMI) and the presence of medical complexity.

RESULTS

Of 361,755 children (median age 8.2 years, IQR 2.5-14.2 years; 51.5% male), 59,283 (16.4%) were seen in the ED. Length was measured or available in 21,330 (36.0%) patients in the ED and 293,410 (97%) patients in clinics. The Broselow tape outperformed all methods, with 50.7% estimates within 10% of measured weight, 80.0% estimates within 20% of measured weight, the lowest MAE (2.5 kg), and lowest RMSE (4.5 kg). The Antevy formula was the most accurate age-based formula, with 49.2% estimates within 10% of measured weight, 80.1% estimates within 20% of measured weight, MAE of 2.8 kg, and RMSE of 4.7 kg. Estimates became less accurate as BMI and estimated weight increased for all methods. Among children with medical complexity (14.1%), the Broselow tape consistently outperformed age-based formulae, with 47.7% estimates within 10% of measured weight, 77.1% estimates within 20% of measured weight, MAE of 2.6 kg, and RMSE of 5.4 kg. The Antevy formula remained the most accurate age-based method among children with medical complexity.

CONCLUSION

The Broselow tape predicted weight most accurately in this large sample of children, including among those with medical complexity. The Antevy formula is the most accurate age-based method for pediatric weight estimation.

Development and Validation of a Weight Estimation Tool for Acutely Ill Children Who Cannot be Weighed

OBJECTIVES

To develop and validate weight estimation tools using mid upper arm circumference (MUAC) and body length, and determine accuracy and precision of Broselow tape in children 6 mo to 15 y of age.

METHODS

Data of 18,456 children aged 6 mo to 5 y and 1420 children aged 5 to 15 y were used to develop linear regression equations using length and MUAC to estimate weight. These were validated on prospectively enrolled populations of 276 and 312 children, respectively. Accuracy was measured by Bland-Altman bias, median percentage errors, and percentage of predicted weight within 10% of true weight. Broselow tape was tested on the validation population.

RESULTS

Gender specific equations were developed which estimated weight within 10% of true weight in 69.9% (64.1-75.2%) and 65.7% (60.1-70.9%) of children aged 6 mo to 5 y, and 5 to 15 y, respectively. Broselow tape predicted weight within 10% of the true weight in 40.5% (34.7-46.6%) and 32.5% (26.7-38.7%) of children aged 6 mo to 5 y and 5 to 15 y, respectively.

CONCLUSIONS

The model developed from MUAC and length accurately estimated weight in children aged 6 mo to 15 y, and is potentially useful during emergencies. The Broselow tape frequently overestimated weight in authors' setting.

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.

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.

Addition of Midthigh Circumference Improves Predictive Ability of Broselow Tape Weight Estimation

OBJECTIVES

This study aimed to improve the accuracy of Broselow tape (BT) weight prediction by adding midthigh circumference (MTC) and to compare and standardize the methods for measuring MTC.

METHODS

This prospective, observational study was conducted in a pediatric emergency department of a tertiary care children's hospital. Children up to 12 years of age presenting to emergency department were included. Children were excluded if obtaining the data would interfere with their acute management. The data collected included MTC, height, BT weight, and actual weight. Three models were built. Broselow tape-only model and MTC plus BT model used 2 methods for MTC measurements: visual approximation of thigh midpoint (visual MTC1) and Centers for Disease Control and Prevention (CDC)-defined method (CDC MTC2).

RESULTS

A total of 430 children were enrolled during pre-coronavirus disease era. Of these, 234 were boys (54.4%) and 196 (45.6%) were girls. Data were categorized into children younger than 2 years (224 [52.1%]) and older than 2 years (206 [47.9%]). African American constituted 250 (58%); White, 136 (31%); and unspecified, 27 (6%). For the entire cohort, both models that included MTC were significantly better at weight prediction with larger adjusted R2 (visual MTC1, 0.921; CDC MTC2, 0.928) and smaller root mean squared (RMSE) (visual MTC1, 2.70; CDC MTC2, 2.56) compared with BT-only model (adjusted R2 = 0.843; RMSE, 3.80). Midthigh circumference plus BT models performed even better in children older than 2 years compared with BT-only model with adjusted R2 (visual MTC1, 0.859; CDC MTC2, 0.872 vs 0.616) and RMSE (visual MTC1, 3.18; CDC MTC2, 3.03 vs 5.27).

CONCLUSIONS

The inclusion of MTC with BT resulted in a more accurate weight prediction in children especially greater than 2 years old. Midthigh circumference model using CDC-defined method was slightly better predictor of actual weight than visual approximation.

Utility of Body Habitus Parameters to Determine and Improve the Accuracy of the Broselow Tape

OBJECTIVES

The aims of this study were to determine and improve accuracy of the Broselow Tape (BT) in estimating children's weight by adding body habitus parameters.

METHODS

This cross-sectional study was conducted in an urban hospital pediatric clinic. Children up to 8 years old coming in for well-child visit were included. Children with acute illness or presence of any chronic condition potentially resulting in growth disturbance and out of BT height range were excluded. The following body habitus parameters were measured using the Centers for Disease Control and Prevention guidelines: actual weight, predicted weight using BT (BTW), mid-thigh circumference (MTC), body mass index, mid-arm circumference, and waist-to-hip ratio.

RESULTS

A total of 301 children were enrolled. Of these, 151 were male (50%). Hispanics constituted 160 (53.2%). There was a positive linear association between BTW and actual weight in the overall cohort (adjusted R2 = 0.9164, P < 0.001). However, there was a difference in this association among children younger than 2 years and children older than 2 years (adjusted R2 = 0.89 vs 0.4841). Incorporating MTC and/or waist circumference along with BTW in the model increased the accuracy, providing a better estimate of actual weight (adjusted R2 = 0.94, P < 0.001).

CONCLUSIONS

We conclude that there might be inaccuracies in the weight predicted by BT in our patient population, especially those weighing more than 15 kg and older than 2 years. Our study also demonstrates that MTC correlates closely with the actual weight and could be used in addition to BT for more accurate weight estimation.

Validity of Broselow tape for estimating the weight of children in pediatric emergency: A cross-sectional study

OBJECTIVE

To assess the validity of the Broselow tape in estimating the weight of Chinese children in pediatric emergency.

METHODS

A cross-sectional study was conducted in the emergency department of the Children's Hospital of Zhejiang University School of Medicine (Hangzhou, Zhejiang Province, China) in March 2022. Broselow tape was used to estimate weight and its validity was compared with the advanced child life support (APLS) method.

RESULTS

The study included 442 children (mean age: 48 months; male-to-female ratio: 1.13:1). The < 10, 10-19 and > 19-kg groups included 44, 257, and 141 children, respectively. The color concordance rates of the Broselow tape-estimated weight in the three groups were 56.8, 57.2, and 68.1%, respectively. The percentage of weight estimations within 10% of actual weight were 65.8% (59.1, 65.8, and 68.1% for the <10, 10-19 and > 19-kg groups, respectively) and 44.8% (40.9, 50.6, and 35.5% for the < 10, 10-19 and > 19-kg groups, respectively) using the Broselow tape and the APLS method, respectively. The correlation between the Broselow tape estimated weight and actual weight was r = 0.931 (P < 0.0001, 95% CI: 0.918-0.943), while the correlation between actual weight and the APLS method calculated weight was r = 0.883 (P < 0.0001, 95% CI: 0.861-0.902). The mean percentage error using the Broselow tape was 1.0 ± 12.0% (P < 0.001 vs. -7.2 ± 17.2% of the APLS method).

CONCLUSION

The Broselow tape may be an available method for predicting the weights of Chinese children in pediatric emergency.

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

Pediatric weight estimation: validation of the PAWPER XL tape and the PAWPER XL tape mid-arm circumference method in a South African hospital

Objective

The primary aim of this study was to prospectively compare the performance of the Broselow tape, Mercy method, pediatric advanced weight prediction in the emergency room extra-long (PAWPER XL) tape, and PAWPER XL mid-arm circumference (MAC) method in estimating the weight of children from a low-income setting. The secondary aim was to analyze the time taken to perform each method.

Methods

This analyzed a convenience study sample of 300 children aged 0 to 18 years at the Baragwanath Hospital in South Africa. Weight estimations were obtained using each of the weight estimation systems on each child. These weight estimations were then compared against the actual weight to determine bias, precision, and accuracy of the estimation methods.

Results

The PAWPER XL tape and PAWPER XL-MAC methods performed the best and provided estimated weights within 10% of the actual weight in 62.7% and 67.3% of cases, respectively, followed by the Mercy method (56.5%) and Broselow tape (43.9%). The use of MAC improved the accuracy of estimation, especially in heavier and taller children. The median times taken to perform measurements using the Broselow tape, Mercy method, PAWPER XL tape, and PAWPER XL-MAC method were 11.3 seconds, 34.7 seconds, 9.3 seconds, and 33.9 seconds respectively.

Conclusion

The PAWPER XL tape and PAWPER XL-MAC methods were the most accurate methods of estimating weight in this group of children. These methods may be considered in preference to the Broselow tape or the Mercy method for emergency weight estimation in low socioeconomic status populations.

Roll up the tape? Laser and optical technologies improve paediatric weight estimation

BACKGROUND

A robust estimation method is needed to prevent medication dosing and equipment sizing errors and improve time to administration during paediatric resuscitation. An electronic measurement with computer interface may improve accuracy and alleviate cognitive burden. This study evaluates the accuracy of two electronic height measurement methods, a laser and an optical device, and compares them to the Broselow™ Pediatric Emergency Tape (BT) for weight estimation.

METHODS

We enrolled children ages 0-14 years from the emergency department of a free-standing, academic children's hospital. We obtained sex, body habitus, true weight, true height, BT colour, and experimental heights. We converted experimental height measurements into weight estimates using standardised growth charts. We calculated Pearson correlations between experimental and actual measurements and the percentages of weight estimates within 10% and 20% of true weights. We repeated analyses on a restricted cohort of children 0-11 years, the intended BT age range.

RESULTS

We enrolled 198 children. The laser, optical device and BT weight estimates had strong positive correlations with the actual weight measurements with Pearson's correlation coefficients of 0.946, p < 0.0001, 0.965, p < 0.0001, and 0.825, p < 0.0001 respectively. 47.8% of optical weight estimates fell within 10% of actual weight and 80.6% within 20%, compared to 40.5% and 75.4% of laser estimates and 39.8% and 65.1% of BT estimates.

CONCLUSION

Electronic-based weight estimates were more accurate than the BT. The accuracy of medication dosing and equipment sizing during paediatric resuscitation may be improved by integrating optical height-based weight estimates with electronic clinical decision support.

Accuracy of weight estimation methods in adults, adolescents and children: a prospective study

INTRODUCTION

Weight estimation of both adult and paediatric patients is often necessary in emergency or low-resource settings when it is not possible to weigh the patient. There are many methods for paediatric weight estimation, but no standard methods for adults. PAWPER and Mercy tapes are used in children, but have not been assessed in adults. The primary aim of this study was to assess weight estimation methods in patients of all ages.

METHODS

Patients were prospectively recruited from emergency and outpatient departments in Kigali, Rwanda. Participants (or guardians) were asked to estimate weight. Investigators collected weight, height, mid-arm circumference (MAC) and humeral-length data. In all participants, estimates of weight were calculated from height and MAC (PAWPER methods), MAC and humeral length (Mercy method). In children, Broselow measurements and age-based formulae were also used. The primary outcome measure was the proportion of estimates within 20% of actual weight (p20).

RESULTS

We recruited 947 participants: 307 children, 309 adolescents and 331 adults. For p20, the best methods were: in children, guardian estimate (90.2%) and PAWPER XL-MAC (89.3%); in adolescents, PAWPER XL-MAC (91.3%) and guardian estimate (90.9%); in adults, participant estimate (98.5%) and PAWPER XL-MAC (83.7%). In all age groups, there was a trend of decreasing weight estimation with increasing actual weight.

CONCLUSION

This prospective study of weight estimation methods across all age groups is the first adult study of PAWPER and Mercy methods. In children, age-based rules performed poorly. In patients of all ages, the PAWPER XL-MAC and guardian/participant estimates of weight were the most reliable and we would recommend their use in this setting.

"Weighing Cam": A New Mobile Application for Weight Estimation in Pediatric Resuscitation

Objective: We evaluated the validity of a newly developed mobile application (i.e. the Weighing Cam) for pediatric weight estimation compared with that of the Broselow tape. Methods: We developed an application that estimates the weight of pediatric patients using a smartphone camera and displays the drug dosage, device size, and defibrillation energy on the screen of the smartphone. We enrolled a convenience sample of pediatric patients aged <16 years who presented at two pediatric emergency departments of two tertiary academic hospitals in South Korea. The pediatric patients' heights and weights were measured; then, one researcher estimated the weights using the application. Using the measured height, we determined the weight estimated by the Broselow tape. We compared the estimated measurements by determining the mean percentage error (MPE), mean absolute percentage error, root mean square percentage error, and percentages predicted within 10% and 20% of the actual. Results: In total, 480 patients were enrolled in 16 age categories, each with 15 males and 15 females of different ages. The Weighing Cam demonstrated a lower bias (mean difference: -1.98% [95% confidence interval -2.91% to -1.05%] for MPE) and a higher proportion of estimated weights within 10% of the actual weights than the Broselow tape (mean difference: 9.1% [95% confidence interval 3.0% to 15.1%]). The Weighing Cam showed better performance in terms of accuracy and precision than the Broselow tape in all subgroups stratified by age or body mass index percentile. Conclusions: The Weighing Cam may estimate pediatric patients' weights more accurately than the Broselow tape. The Weighing Cam may be useful for pediatric resuscitation in both prehospital and hospital settings.

Accuracy of Broselow tape in estimating the weight of the child for management of pediatric emergencies in Nepalese population

Background

Children with emergency conditions require immediate life-saving intervention and resuscitation. Unlike adults, the pediatric emergency drug dose, equipment sizes, and defibrillation energy doses are calculated based on the weight of the individual child. Broselow tape is a color-coded length-based tape that utilizes height/weight correlations for children. However, in low-income countries like Nepal, due to factors like undernutrition, the Broselow tape may not accurately estimate weight in all ranges of pediatric age group.

Methods

This study was conducted in the Department of Pediatrics of Dhulikhel Hospital, Kathmandu University Teaching Hospital, in children less than 15 years of age. Our study aims to prospectively compare the actual weights of urban and rural Nepalese children with the estimated weights using the Broselow tape (2017 edition) and the updated APLS formula. The errors in the selection of endotracheal tube size and adrenaline dose using the Broselow tape were also explored.

Results

This study included 315 children with male to female ratio of 0.63:1. They were divided into 3 groups according to their estimated weight by the Broselow tape into < 10 kg, 10–18, and > 18 kg. There was a total agreement of the estimated color zone according to the Broselow tape with the actual weight in the gray zone (p = 0.01). There was a positive relationship between the actual body weight and the estimated body weight (correlation (r = 0.970, p = 0.01) and accuracy (r² = 0.941)). Our analysis showed that the accuracy of estimated weight with the Broselow tape decreases with increasing weight of children. The precision of the tape was relatively high in the lower length zones as compared to the higher length zones. The estimated size of the endotracheal tube (p = 0.01) and adrenaline dose (p = 0.08) by the Broselow tape was in agreement with that estimated using PALS formula in weight group of less than 18 kg, but decreases as the estimated weight increases further.

Conclusions

The accuracy of the Broselow tape in estimating the weight of a child, endotracheal tube size, and dose of adrenaline is higher in weight group of less than 18 kg, and accuracy decreases as the weight of child increases. The Broselow tape should be avoided in children weighing more than 18 kg. Hence, PALS age-based formula for ET tube size estimation and weight-based formula for adrenaline dose calculation are recommended for children weighing more than 18 kg.

Validation and human factor analysis study of an infant weight estimation device

Background

Weight is critical for the medical management of infants; however, scales can be unavailable or inaccessible in some practice settings. We recently developed and validated a robust infant weight estimation method based on chest circumference (CC) and head circumference (HC). This study was designed to determine the human factors (HF) experience with, and predictive performance of, an infant weight estimation device that implements this method.

Methods

Prospective, multi-center, observational, masked study of 486 preterm and term infants (0–90 days) assessed by 15 raters. Raters measured the infant using calibrated scales/measures and masked versions of the device. Raters also evaluated critical tasks associated with device use. Mean error (ME) and mean percentage error (MPE) were used to assess predictive performance.

Result

Among 486 infants enrolled (36.8 ± 4.0 weeks gestational age, 31.5 ± 28.6 days postnatal age), predicted weight correlated highly with actual weight (r = 0.97, ME: − 69 ± 257 g, MPE: − 1.3 ± 6.9%). Predicted weight was within 10 and 15% of actual weight in 86 and 99%, of infants. HF errors were low, 0.1–0.8% depending on task. In all cases raters were confident or very confident in their measurements.

Conclusion

The device was statistically equivalent to the method on which it was based and approximated weight with acceptable variance from the true weight. HF data suggest the device is easy to use. This device can be used to estimate weight in infants when calibrated scales are impractical or unavailable.

Mercy TAPE for Calculation-Free Height Estimation in Pediatric Rehabilitation Patients

BACKGROUND

In children, height is an essential element of a pediatric assessment, yet this measure is less likely to occur in nonambulatory children or those with unique disabilities. There is compelling support for surrogate measures; however, many of these are accompanied by limitations.

OBJECTIVE

This study was conducted to evaluate whether the U.S. Food and Drug Administration (FDA)-cleared Mercy TAPE could be adopted for height estimation.

DESIGN

Development and external validation of a height-estimation method were conducted with retrospectively collected data in nonrehabilitation children. Testing of the model was performed prospectively in a pediatric rehabilitation population.

SETTING

U.S. pediatric rehabilitation outpatient clinic.

PARTICIPANTS

Data from 19 407 children were used to develop the model. Data from an independent cohort of 1472 children were used for external validation, and the model was tested in 195 pediatric rehabilitation patients. Of the 195 patients, 57% required no wheelchair, 18% could ambulate independently for short distances, 17% could ambulate with an assistive device, and 8% were full-time wheelchair users.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASUREMENTS

Relative error (RE), percentage error (PE), and percent predicted within 10% and 20% of actual height.

RESULTS

Height estimated with the modified Mercy TAPE was highly predictive of actual height in nonrehabilitation children in the United States (RE [mean ± SD]: 1.1 ± 5.7 cm; PE [mean ± SD]: 1.0 ± 4.7%). In rehabilitation patients, height was underestimated to a greater extent (RE [mean ± SD]: 3.0 ± 7.4 cm; PE [mean ± SD]: -2.1 ± 5.6%).

CONCLUSIONS

The Mercy TAPE offers a reasonable approximation of height in ambulatory children, although it slightly underestimates height in the pediatric rehabilitation population. Consequently, this and other surrogate measures may be less suited to examining growth against a reference ambulatory population and more suited to following individual children over time.

A Comparison of Pediatric Weight Estimation Methods for Emergency Resuscitation

OBJECTIVES

Obtaining accurate pediatric weight is necessary during emergency resuscitation. Although several weight estimation methods exist, the most precise method has not been conclusively determined. This study aimed to evaluate the validity, reliability, and practicality of these tools.

METHODS

A prospective observational study was conducted in healthy Thai children aged 6 months to 12 years. Correlations between estimated and actual weights were tested. Validity was assessed by mean bias (estimated weight minus actual weight) and accuracy (10% error). Practicality was evaluated by time usage and data derived from user questionnaires.

RESULTS

Four hundred thirty participants with mean age of 6.7 years and mean weight of 26 kg were enrolled. A strong correlation between estimated weight and actual weight in all methods was demonstrated. Parental estimation was the most accurate tool in all age groups, with the lowest overall mean error (ME) of -0.83 kg and the highest accuracy of 88.7%. The Broselow tape was the second most accurate tool in ages younger than 1 year and 1-to-5-year age groups (ME = 0.23 and 0.50 kg; accuracy = 55.3% and 54.1%, respectively). The Mercy method was the second most accurate tool in the 6-to-10-year and 11-to-12-year age groups (ME = -2.47 and -2.77; accuracy = 54.6% and 67.9%, respectively). The Broselow tape had the highest score for practicality of use.

CONCLUSIONS

Parental estimation was the most accurate method in every age group. The next best alternative is the Broselow tape in children aged 5 years or younger and the Mercy method in children aged older than 5 years.

Development of regression equations for estimating height and weight using body segments in Argentine children

OBJECTIVES

Body weight and height measurements are essential in children for assessing growth and nutrition, for the calculation of medication doses, and for the effectiveness of medical interventions. When direct measurements cannot be made, segmental measures can be used to estimate weight and height. The equations available to estimate height and weight, however, are limited. The aim of this study was to use segmental measures to develop equations for use in pediatric clinical practice.

METHODS

A cross-sectional study design was used to collect data from 861 healthy children (484 females and 377 males) ages 2 to 18 y to develop equations for estimating weight and height from midarm circumference (MAC) and knee-heel height (KH), respectively. A multi-linear regression model was used to develop the equations.

RESULTS

The high correlation between MAC and the actual weight and KH and height indicates strong agreement. Four equations were developed to estimate weight and height using segmental measures. 1. To estimate weight from MAC for females: W = 2.37 × MAC + 1.64 × age (y) - 28.28. 2. To estimate weight for males: W = 2.54 × MAC + 1.82 × age (y) - 32.73. 3. To estimate height from KH for females: H = 2.88 × KH + 0.15. 4. To estimate height from KH for males: H = 2.73 × KH + 0.21.

CONCLUSIONS

MAC and KH can be used for estimation equations for weight and height with a very good predictive power. Sex and age were significant covariates in estimating weight. To predict height, only sex was needed to fit the model.

The accuracy of paediatric weight estimation during simulated emergencies: The effects of patient position, patient cooperation, and human errors

INTRODUCTION

The effect of patient position and patient cooperation on the accuracy of emergency weight estimation systems has not been evaluated previously. The objective of this study was to evaluate weight estimation accuracy of the Broselow tape, the PAWPER XL tape, the Mercy method, and a custom-designed mobile phone App in a variety of realistic simulated paediatric emergencies.

METHODS

This was a prospective study in which 32 emergency medicine volunteers participated in eight simulations of common paediatric emergency conditions, using children models. The participants used each of the four methods to estimate the children's weight. The accuracy of and time taken for the weight estimations were evaluated for each method. A regression analysis determined the effects of patient position and cooperation on weight estimation accuracy. Evaluation of subgroups of best-performers and worst-performers among the participants provided information on the effects of human user-error on weight estimation accuracy.

RESULTS

The Broselow tape, Mercy method, App and the PAWPER XL tape achieved percentages of weight estimation within 10% of actual weight in 47.7, 57.3, 68.1, and 73.0% of estimations, respectively. Patient position and cooperation strongly impacted the accuracy of the Broselow tape, had a minimal effect on the Mercy method and the App, and had no effect on the PAWPER XL tape. The best performing participants achieved very high accuracy with all methods except the Broselow tape.

DISCUSSION

The Mercy method, the App, and the PAWPER XL tape achieved exceptionally high accuracy even in uncooperative and sub-optimally positioned children when used by the best-performing participants. Human error, from inexperience and inadequate training, had the most significant impact on accuracy. The Mercy method was the most subject to human error, and the PAWPER XL tape, the least. Adequate training in using weight estimation systems is essential for paediatric patient safety.

Estimating the weight of children in Nepal by Broselow, PAWPER XL and Mercy method

BACKGROUND

Resuscitation of a critically-ill child requires an accurate weight for fluids and medication dosing; however, weighing children on a scale while critically ill is not always practical. The objective of this study is to determine the accuracy of three different weight estimation methods (Broselow, PAWPER XL and Mercy tape) of children presenting to Patan Hospital, Nepal.

METHODS

This was a prospective, cross-sectional study that included children presenting to the emergency department and under-fourteen outpatient clinic at Patan Hospital. Measured weight was compared to estimated weight of Broselow, PAWPER XL, and Mercy tapes. The mean percentage error and percentage of estimated weights that were within 10% (PW10) and 20% (PW20) of actual weight were calculated. Acceptable accuracy was determined as a PW10>70% and PW20>95%. A Bland-Altman analysis was done to determine agreement between each weight estimation method and actual weight.

RESULTS

The study included 813 children. The mean age was 4.2 years (ranging from 4 days to 14 years) with 60% male. The mean percentage error (MPE) for Broselow, PAWPER XL and Mercy were -1.0% (SD 11.8), 0.7% (10.5) and 4.2% (11.9) respectively. The predicted weight within 10% was highest for the PAWPER XL (71.5%) followed by Broselow (63.2%) and Mercy (58.1%). The predicted weight within 20% of actual weight was 95.2%, 91.5% and 91.3% for PAWPER XL, Broselow and Mercy respectively.

CONCLUSION

The PAWPER XL tape was the only method found to be accurate in estimating the weight of Nepalese children.

Paediatric weight estimation by age in the digital era: optimising a necessary evil

BACKGROUND

Age-based weight estimation methods are regularly used in paediatric emergency medicine despite their well-established inaccuracy.

AIM

Determine the potential improvement in accuracy achievable by the use of a new mobile application, based on CDC/WHO weight-for-age centile data, which incorporates a gender assignment, a body habitus assessment, and which is capable of an age-in-months based calculation.

METHODS

A theoretical, simulated validation study, comparing the performance of the widely used APLS/EPALS formulae against two contemporary habitus-adjusted methods, and the Helix Weight Estimation Tool. 1,070,743 children from the 2015/2016 UK National Child Measurement Program dataset, aged between 4 and 5 and 11 and 12 years, had age-based weight estimates made by all five methods.

RESULTS

Primary outcomes were the percentage of weight estimations within 10%, 20%, and those greater than 20% discrepant from actual weight for each method. Our theoretical, gender-dependent, habitus-adjusted method performed better than all other methods across all error thresholds. The overall number of estimations within 10% was 70.4%, and within 20% was 95.45%. The mean percentage error was -1% compared to actual weight.

CONCLUSION

The use of a digital tool incorporating a subjective assessment of body habitus, gender assignment, and the ability to estimate weight based on age-in-months might be able optimise the process of paediatric weight estimation by age, making this practice as safe and accurate as possible for the occasions when weight estimation by age is chosen over length-based methods.

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.

Comparative Performance of Pediatric Weight Estimation Techniques: A Human Factor Errors Analysis

OBJECTIVE

We compared performance characteristics of 7 weight estimation methods examining predictive performance and human factors errors.

METHODS

This was a prospective study of 80 emergency care providers (raters) and 80 children aged 2 months to 16 years. Raters estimated weights in 5 children with the following 7 strategies: visual estimation, Advanced Pediatric Life Support, Luscombe and Owens, Broselow tape, devised weight estimation method, 2D Mercy TAPE (2DT), and 3D Mercy TAPE (3DT). Quantitative errors were determined by checking rater values against values returned with optimal method use.

RESULTS

Four hundred rater-child pairings generated 2800 weight estimates. For all methods, rater-estimated weights were less accurate than weights derived by optimal application. Skill-based, perception, and judgment/decision error were observed. For visual estimation, weights were underestimated in most children. For Advanced Pediatric Life Support/Luscombe and Owens, order of operations markedly impacted errors with 23% of calculations requiring addition first performed incorrectly versus 9% of calculations requiring multiplication first. For Broselow tape, only 63% of cases were eligible for estimation with this device, yet raters assigned a weight in 96% of cases. For Devised Weight Estimation Method, 96% of overweight and 48% of obese children were classified as slim or average. For 2DT/3DT, the 2DT was prone to more errors most commonly use of the wrong side of the device (24%). The impact of rater characteristics on error was most pronounced for methods requiring calculation.

CONCLUSIONS

Skill-based, perception, or judgment errors were observed in more than 1 of 20 cases. No singular strategy was used with 100% accuracy.

Validity of Broselow tape for estimating weight of Indian children

BACKGROUND & OBJECTIVES

The Broselow tape has been validated in both ambulatory and simulated emergency situations in the United States and is believed to reduce complications arising from inaccurate drug dosing and equipment sizing in paediatric population. This study was conducted to determine the relationship between the actual weight and weight determined by Broselow tape in the Indian children and to derive an equation for determination of weight based on height in the Indian children.

METHODS

This cross-sectional study was conducted at a tertiary care hospital in Mumbai, India. The participants' weights were divided into three groups <10 kg, 10-18 kg and >18 kg with a total sample size estimated to be 210 (70 in each group). Using the tape, the measured weight was compared to Broselow-predicted weight and percentage weight was calculated. Accuracy was defined as agreement on Broselow colour-coded zones, as well as agreement within 10 per cent between the measured and Broselow-predicted weights. The resulting data were compared with weights estimated by advanced paediatric life support (APLS) and updated APLS formulae using Pearson's correlation coefficient.

RESULTS

The mean percentage differences were -11.78, -17.09 and -14.27 per cent for <10, 10-18 and >18 kg weight-based groups, respectively. The Broselow colour-coded zone agreement was 33.3 per cent in children weighing <10 kg, but only 7.4 per cent in the 10-18 kg group and 33.9 per cent in the >18 kg group. Agreement within 10 per cent was 53.13 per cent for the <10 kg group, but only 21.08 per cent for the 10-18 kg group and 33.9 per cent for the >18 kg group. Application of 10 per cent weight correction factor improved the percentages to 79.2 per cent for the <10 kg category, to 55.70 per cent for the 10-18 kg group and to 61.0 per cent for the >18 kg group. The correlation coefficient between actual weight and weights estimated by Broselow tape (r=0.89) was higher than that between actual weight and weight estimated by APLS method or updated APLS formulae (r=0.68) in 12-60 months age group as well as in >60 months age group (r=0.76).

INTERPRETATION & CONCLUSIONS

Broselow weight overestimated weight by >10 per cent in majority of Indian children. The weight overestimation was greater in children belonging to over 18 and 10-18 kg weight groups. Applying 10 per cent weight correction factor to the Broselow-predicted weight may provide a more accurate estimation of actual weight in children attending public hospital. Weights estimated using Broselow tape correlated better with actual weights than those calculated using APLS and updated APLS formulae.

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.

Construction of Lambda, Mu, Sigma Values for Determining Mid-Upper Arm Circumference z Scores in U.S. Children Aged 2 Months Through 18 Years

BACKGROUND

Mid-upper arm circumference (MUAC) has proven highly predictive of morbidity and mortality associated with malnutrition better, in some cases, than other growth indicators, including body mass index (BMI) z scores and weight-for-height z scores. A recent consensus statement recommended the inclusion of MUAC and MUAC z scores in the nutrition assessment of children in the United States; however, the requisite data to permit z score calculations for children aged >5 years have not been published.

OBJECTIVE

This investigation was designed to generate lambda mu sigma (LMS) values to permit the calculation of MUAC z scores in U.S. children 2 months through 18 years of age.

DESIGN

Anthropometric data from the Centers for Disease Control and Prevention (CDC) National Health and Nutrition Examination Survey (1999-2012) were used for model development (n = 28,995). Smoothed centiles were constructed and compared with previously described CDC percentiles. Independently collected MUAC data from 2 different U.S. studies were used for external validation (n = 1438).

STATISTICAL ANALYSES

Goodness-of-fit was assessed visually and statistically by examining detrended quantile-quantile plots, Q statistics, and the distribution of z scores.

RESULTS

The curves generated in this investigation fit the raw data well with no systematic bias and no sacrifice in fit for children aged <12 months. The curves were consistent with those published by the CDC, and the distribution z scores approximated 0 ± 1 in all age groups.

CONCLUSIONS

These LMS values derived in this investigation can be used by clinicians to generate MUAC z scores for U.S. children.

An assessment of the accuracy of a novel weight estimation device for children

BACKGROUND

We sought to validate the accuracy and assess the efficacy of a newly developed electronic weight estimation device (ie, the rolling tape) for paediatric weight estimation.

METHODS

We enrolled a convenience sample of children aged <17 years presenting to our emergency department who volunteered to participate in the study. The children's heights and weights were measured, and three researchers estimated these values using the rolling tape and Broselow tape at 5 min intervals. The weight estimates of researcher 1, researcher 2 and the Broselow tape were compared with measured values, and mean percentage error (MPE), root mean square error (RMSE) and percentage of estimates within 10% of the actual measured values were calculated. For 30 randomly selected subjects, we compared the time interval from the start of the measurement to the time that orders for epinephrine, defibrillation dose and instrument size could be given in a simulated arrest scenario.

RESULTS

We enrolled 906 children (median age 4.0 years). For researcher 1, researcher 2 and the Broselow tape, MPE values were 0.11% (RMSE 2.61 kg), 1.41% (RMSE, 2.61 kg) and 1.72% (RMSE 5.41 kg), respectively, and the percentages of children with predictions within 10% of their actual weight were 75.1%, 75.7% and 60.6%, respectively. In the 30 simulated cases, the mean time for measurement to ordering was significantly shorter (25.8 s vs 35.5 s, p<0.001) for the rolling tape compared with the Broselow tape method.

CONCLUSIONS

The rolling tape is a good weight estimation tool for children compared with other methods. The rolling tape method significantly decreased the time from weight estimation to orders for essential drug dose, instrument size and defibrillation dose for resuscitation.

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.

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.

Accuracy of the Broselow Tape in South Sudan, "The Hungriest Place on Earth"

OBJECTIVES

The Broselow tape is a length-based tool used for the rapid estimation of pediatric weight and was developed to reduce dosage-related errors during emergencies. This study seeks to assess the accuracy of the Broselow tape and age-based formulas in predicting weights of South Sudanese children of varying nutritional status.

METHODS

This was a retrospective, cross-sectional study using data from existing acute malnutrition screening programs for children less than 5 years of age in South Sudan. Using anthropometric measurements, actual weights were compared with estimated weights from the Broselow tape and three age-based formulas. Mid-upper arm circumference was used to determine if each child was malnourished. Broselow accuracy was assessed by the percentage of measured weights falling into the same color zone as the predicted weight. For each method, accuracy was assessed by mean percentage error and percentage of predicted weights falling within 10% of actual weight. All data were analyzed by nutritional status subgroup.

RESULTS

Only 10.7% of malnourished and 26.6% of nonmalnourished children had their actual weight fall within the Broselow color zone corresponding to their length. The Broselow method overestimated weight by a mean of 26.6% in malnourished children and 16.6% in nonmalnourished children (p < 0.001). Age-based formulas also overestimated weight, with mean errors ranging from 16.2% over actual weight (Advanced Pediatric Life Support in nonmalnourished children) to 70.9% over actual (Best Guess in severely malnourished children).

CONCLUSIONS

The Broselow tape and age-based formulas selected for comparison were all markedly inaccurate in both the nonmalnourished and the malnourished populations studied, worsening with increasing malnourishment. Additional studies should explore appropriate methods of weight and dosage estimation for populations of low- and low-to-middle-income countries and regions with a high prevalence of malnutrition.

Improving antibiotic prescribing for children in the resource-poor setting

Antibiotics are a critically important part of paediatric medical care in low- and middle-income countries (LMICs), where infectious diseases are the leading cause of child mortality. The World Health Organization estimates that >50% of all medicines are prescribed, dispensed or sold inappropriately and that half of all patients do not take their medicines correctly. Given the rising prevalence of antimicrobial resistance globally, inappropriate antibiotic use is of international concern, and countries struggle to implement basic policies promoting rational antibiotic use. Many barriers to rational paediatric prescribing in LMICs persist. The World Health Organization initiatives, such as 'Make medicines child size', the Model List of Essential Medicines for Children and the Model Formulary for Children, have been significant steps forward. Continued strategies to improve access to appropriate drugs and formulations, in conjunction with improved evidence-based clinical guidelines and dosing recommendations, are essential to the success of such initiatives on both a national and an international level. This paper provides an overview of these issues and considers future developments that may improve LMIC antibiotic prescribing.

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.

Evaluation of the Mercy weight estimation method in Ouelessebougou, Mali

Background

This study evaluated the performance of a new weight estimation strategy (Mercy Method) with four existing weight-estimation methods (APLS, ARC, Broselow, and Nelson) in children from Ouelessebougou, Mali.

Methods

Otherwise healthy children, 2 mos to 16 yrs, were enrolled and weight, height, humeral length (HL) and mid-upper arm circumference (MUAC) obtained by trained raters. Weight estimation was performed as described for each method. Predicted weights were regressed against actual weights. Agreement between estimated and actual weight was determined using Bland-Altman plots with log-transformation. Predictive performance of each method was assessed using residual error (RE), percentage error (PE), root mean square error (RMSE), and percent predicted within 10, 20 and 30% of actual weight.

Results

473 children (8.1 ± 4.8 yr, 25.1 ± 14.5 kg, 120.9 ± 29.5 cm) participated in this study. The Mercy Method (MM) offered the best correlation between actual and estimated weight when compared with the other methods (r² = 0.97 vs. 0.80-0.94). The MM also demonstrated the lowest ME (0.06 vs. 0.92-4.1 kg), MPE (1.6 vs. 7.8-19.8%) and RMSE (2.6 vs. 3.0-6.7). Finally, the MM estimated weight within 20% of actual for nearly all children (97%) as opposed to the other methods for which these values ranged from 50-69%.

Conclusions

The MM performed extremely well in Malian children with performance characteristics comparable to those observed for U.S and India and could be used in sub-Saharan African children without modification extending the utility of this weight estimation strategy.