To compare the accuracy of the Broselow-Luten Tape and APLS, Theron and Shann’s formulae in prediction of weight in children aged 5 to 10 years in Auckland
Paediatric weight estimation methods commonly used in emergency situations tend to underestimate the weight of most children. This study aims to test the accuracy of four weight estimation methods used in New Zealand to predict a child’s weight in an emergency situation.
This study was a prospective, observational study where data was collected over two weeks in July 2013 at 5 Auckland primary schools. Children between 5 and 10 years of age had their weight, height and Broselow-Luten tape (2011 version) weight recorded using standardised methods of measurement. Weight estimations were then calculated using age based formula derived by Advanced Pediatric Life Support (APLS), Shann and Theron as well as the length based Broselow-Luten tape. Age, ethnicity, gender and school decile data were collected for stratification. Percent error was calculated for each child and mean bias (actual weight – estimated weight) and Bland-Altman plots created.
Three hundred and seventy six children were included in this study. Theron’s formula (mean bias -6.5) was least accurate clinically with 28.7% of weight estimates within 10% of actual weight. The Advanced Paediatric Life Support (APLS) formula showed positive bias (mean bias 7.8) and 39.1% of weight estimates within 10% of actual weight. Shann’s formula was the most accurate among the age based weight estimation methods (mean bias 7.7) with 45.7% of estimates within 10% of actual weight. The Broselow-Luten tape was accurate within its parameters of 43 to 143 cm (n=305) and in this group of children, was the most accurate (mean bias 1.1) with 73.4% of weight estimates within 10% of actual weight.
The length based Broselow-Luten Tape is the most accurate method of weight estimation for a cross section of Auckland children aged 5 to 10 years who are below the height of 143 cm. Among the age based weight estimation methods, Shann’s formula is the most accurate. These findings have important implications for prehospital and emergency resuscitation policy in New Zealand.