Recently, Cattermole et al. discussed our work as well as the work of
others in a paper describing the proportion of children for whom the
Broselow tape (BT) is not applicable.[1] As the authors point out,
studies that have examined the accuracy of the BT tend to omit from
inclusion, or exclude from analysis, children whose length exceeds the
bounds of the tape. While these studies in effect overestimate the
utility of the BT, children that are too tall for the device are
relatively easy to identify. Consequently, clinical decision makers are
immediately sensitized to the fact that the weight estimate may suffer
from inaccuracies. What may go unidentified by the clinician caring for
the "height-appropriate" child is the fact that the BT is increasingly
less reliable with increasing body mass.[2] This can pose serious
consequences for the medical management of children at the extremes of
weight. When we examined the children from our original NHANES cohort
(n=19,266) that could be classified as overweight/obese per CDC definition
(i.e. 2+ yrs, BMI>85th percentile) (n=4,587),[3] and restricted
evaluation to children who met the length criteria for application of the
BT (n=1,916), we found that the BT predicted only 100 to within 10% of
their actual weight (Table). The BT predicted a comparably small fraction
of obese children to within 20% of their actual weight. By contrast, the
Mercy weight estimation method that incorporates length and MUAC with no
restrictions estimated 81% of overweight children and 74% of obese
children to within 10% of their actual weight.[3] Cattermole et al. state
"it is clear that the accuracy of the BT is only applicable to those whom
it fits," and the proportion of children for whom the BT proves to be a
good "fit" continues to diminish as the waistlines of our pediatric
population expand. We concur that the "most promising options for weight
estimation" will likely include estimates of habitus and believe that
weight estimation methods which are less restrictive, more accurate, and
as user friendly as the BT are critically needed.
Cumulative Percent Overweight Predicted by BT within:
10% of actual weight-11%, 20% of actual weight-85%,
30% of actual weight-99%, 40% of actual weight-100%.
Cumulative Percent Obese Predicted by BT within:
10% of actual weight-0%, 20% of actual weight-18%, 30% of actual weight-
62%, 40% of actual weight-89%,
50% of actual weight-98.5%, 60% of actual weight-99.7%, 70% of actual
weight-100%.
References
1. Cattermole GN, Leung PYM, Graham CA, Rainer TH. To tall for the
tape: the weight of school children who do not fit the Broselow tape.
Emerg Med J 2013 Apr 13. [Epub ahead of print]
2. Lubitz DS, Seidel JS, Chameides L, Luten RC, Zaritsky AL, Campbell
FW. A rapid method for estimating weight and resuscitation drug dosages
from length in the pediatric age group. Ann Emerg Med 1988;17(6):576-81.
3. Abdel-Rahman SM, Ridge AL. An improved pediatric weight estimation
strategy. Open Med Devices J 2012;4:87-97.
Conflict of Interest:
Children's Mercy Hospital owns the rights to IP referenced in this letter. This IP is intended to be made freely available in resource restricted settings
Recently, Cattermole et al. discussed our work as well as the work of others in a paper describing the proportion of children for whom the Broselow tape (BT) is not applicable.[1] As the authors point out, studies that have examined the accuracy of the BT tend to omit from inclusion, or exclude from analysis, children whose length exceeds the bounds of the tape. While these studies in effect overestimate the utility of the BT, children that are too tall for the device are relatively easy to identify. Consequently, clinical decision makers are immediately sensitized to the fact that the weight estimate may suffer from inaccuracies. What may go unidentified by the clinician caring for the "height-appropriate" child is the fact that the BT is increasingly less reliable with increasing body mass.[2] This can pose serious consequences for the medical management of children at the extremes of weight. When we examined the children from our original NHANES cohort (n=19,266) that could be classified as overweight/obese per CDC definition (i.e. 2+ yrs, BMI>85th percentile) (n=4,587),[3] and restricted evaluation to children who met the length criteria for application of the BT (n=1,916), we found that the BT predicted only 100 to within 10% of their actual weight (Table). The BT predicted a comparably small fraction of obese children to within 20% of their actual weight. By contrast, the Mercy weight estimation method that incorporates length and MUAC with no restrictions estimated 81% of overweight children and 74% of obese children to within 10% of their actual weight.[3] Cattermole et al. state "it is clear that the accuracy of the BT is only applicable to those whom it fits," and the proportion of children for whom the BT proves to be a good "fit" continues to diminish as the waistlines of our pediatric population expand. We concur that the "most promising options for weight estimation" will likely include estimates of habitus and believe that weight estimation methods which are less restrictive, more accurate, and as user friendly as the BT are critically needed.
Cumulative Percent Overweight Predicted by BT within: 10% of actual weight-11%, 20% of actual weight-85%, 30% of actual weight-99%, 40% of actual weight-100%.
Cumulative Percent Obese Predicted by BT within: 10% of actual weight-0%, 20% of actual weight-18%, 30% of actual weight- 62%, 40% of actual weight-89%, 50% of actual weight-98.5%, 60% of actual weight-99.7%, 70% of actual weight-100%.
References
1. Cattermole GN, Leung PYM, Graham CA, Rainer TH. To tall for the tape: the weight of school children who do not fit the Broselow tape. Emerg Med J 2013 Apr 13. [Epub ahead of print]
2. Lubitz DS, Seidel JS, Chameides L, Luten RC, Zaritsky AL, Campbell FW. A rapid method for estimating weight and resuscitation drug dosages from length in the pediatric age group. Ann Emerg Med 1988;17(6):576-81.
3. Abdel-Rahman SM, Ridge AL. An improved pediatric weight estimation strategy. Open Med Devices J 2012;4:87-97.
Conflict of Interest:
Children's Mercy Hospital owns the rights to IP referenced in this letter. This IP is intended to be made freely available in resource restricted settings