Ralston and Myatt reported a number of equations for estimated the weight of a small child based on body measurements. One uses mid upper arm circumference (MUAC). The authors are from the Uniformed Services University of the Health Sciences in Bethesda and Brixton Healy in Wales.

Patient selection: child 6 to 59 months in a limited-resource setting.



(1) mid upper arm circumference in mm


estimated weight in kilograms =

= 11.2670 - (X / 0.4401)


X =

= 11.2670 - ((0.1445 * (MUAC)) - 9.0255)


If this is rearranged and consolidated:


estimated weight in kilograms =

= (0.3283 * (MUAC)) - 35

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