To Determine the Accuracy and Reliability of Broselow Tape in Comparison with Actual Weight and Advance Pediatric Life Support Formula Weight Assessment among the Pediatric Population Presenting to Emergency Department of a Low Income Setting

Background: Near precise weight assessment among sick pediatric patients remains a dilemma and conventionally accepted weight assessment methods, in busy ED might be inaccurate or unreliable. Children have different weights at different ages, and accurate/precise weight measurement is of utmost importance for weight-related dose calculation of drugs/fluids, equipment sizes, an accurate dose of electrical currents during cardiac shock, etc.

Several weight estimation methods are available and are dependent on the child's age, length, or both. However, length or length-and-age-based methods may have greater accuracy than merely age-based, still precise weight measurement while children are recumbent (length) has its own challenges.

Objective: We determined the accuracy and reliability of BT by comparing it with actual weight and advanced pediatric life support formula (APLS) among the pediatric population presenting to the emergency department.

Methods: This was a single-center, cross-sectional study design. This study was conducted at pediatric emergency of an urban tertiary care hospital after ethics committee approval and written consent from parents/caregivers during July 2021- June 22.

Pediatric patients aged 1 month to 12 years, weight 3-36 kg, and height 46.5-142.5 cm on BT were included. Actual weight was measured on a standard weighing machine. We use Broselow pediatric emergency tape (2017 edition), APLS formula was also used to measure the estimated weight by using the age provided by parents.

Descriptive analysis, mean and standard deviation were calculated, frequencies and percentages were calculated for categorical variables. Cronbach’s alpha and Passing-Bablok regression analysis was applied to assess the reliability and identify systematic biases between actual body weights with estimated BT. Bland–Altman analysis was also performed to measure the precision, accuracy, and bias.

Results: 250 children were included with equal gender distribution and were divided in to three categories as per the weight estimation by BT in to <10 kg (n=58, 23.2%), 10-18 kg (n=151, 60.4%) and >18 kg (n=41, 16.4%). The mean age was 5.26 (±2.37) years, majority of children were below 5 years of age (n=144, 58%).

Positive agreement between BT weight with actual weight and other formulas in weight category of <10 kg, however as weight increases from 10 kg, onward results are not significant.

Passing and Bablok Regression analysis showed a positive correlation between the estimated and actual (AW) body weight (r=0.9280, p<0.001) and accuracy (r2=0.929), and the accuracy of BT weight decreases with the increasing weight of children.

Similarly, 95% agreement limit and mean biased was 0.465 to 1.113 and 0.789±2.602 between BT and APLS, BT with AW was -0.50 to -0.28 and -0.39±0.885. Comparing and correlating weight assessment of APLS formula vs LF and TF didn't show significance with a p-value of 0.041 and 0.034 respectively.

Bland-Altman plot between BT measurement with AW demonstrates a bias equal to 1.096 kg with a limit of 0.870 to 1.815.

Conclusion: BT may be an accurate and time bound method of weight measurement as compared to other methods of weight estimation, however the accuracy of BT may be adversely affected with age exceeding 95 months and weight >26 kg. BT may be safely used in the younger pediatric population. Health care professionals may consider this information while using BT to estimate weight for pediatric resuscitation, however, this is a single center hospital based study with limited cases, we recommend to have a large scale community based study or a census before to generalize these results to general population.