Are methods used to estimate weight in children accurate?

OBJECTIVE: The exact weight of a child undergoing resuscitation is usually not known. Several methods to estimate a child's weight have been proposed. We evaluated six of these methods to determine their accuracy and clinical usefulness across a range of weights and ages.
METHOD: Children attending a tertiary paediatric emergency department on 30 non-consecutive days were weighed, a length or height was obtained and an estimation of body habitus (slim, average or heavy) made by a single investigator, Karen Black (KB). All children less than 145 cm were also measured using the Broselow tape. Six methods of weight estimation were employed and the calculated weight compared to the true weight. The weight estimation methods evaluated were the advanced paediatric life support (APLS) method, Broselow tape, devised weight estimation method (DWEM), Oakley table, Traub-Johnson and the Traub-Kichen methods.
RESULTS: Four hundred and ninety-five children were included in the study. Children were evenly distributed among the weight groups of less than 10 kg, 10-25 kg, 25-40 kg and over 40 kg. The methods with the best overall performance were the devised weight estimation method and Broselow tape although the latter has a length limitation of 145 cm. The other methods performed well in the middle two weight groups but poorly outside these groups.
CONCLUSIONS: The most accurate methods of weight estimation in children are the Broselow tape and the devised weight estimation method. We recommend the use of either of these methods in emergency situations where direct weighing is not possible.