Mid-Upper Arm Circumference (MUAC) is the circumference of the left upper arm, measured at the mid-point between the tip of the shoulder and the tip of the elbow (olecranon process and the acromium).
MUAC is used for the assessment of nutritional status. It is a good predictor of mortality and in many studies, MUAC predicted death in children better than any other anthropometric indicator. This advantage of MUAC was greatest when the period of follow-up was short.
The MUAC measurement requires little equipment and is easy to perform even on the most debilitated individuals. Although it is important to give workers training in how to take the measurement, the correct technique can be readily taught to minimally trained health workers and community-based volunteers. It is thus suited to screening admissions to feeding programs during emergencies.
MUAC is recommended for use with children between six and fifty-nine months of age and for assessing acute energy deficiency in adults during famine.
The major determinants of MUAC, arm muscle and sub-cutaneous fat, are both important determinants of survival in starvation. MUAC is less affected than weight and height based indices (e.g. WHZ, WHM, BMI) by the localised accumulation of fluid (i.e. bipedal or nutritional oedema, periorbital oedema, and ascites) common in famine and is a more sensitive index of tissue atrophy than low body weight. It is also relatively independent of height and body-shape.
MUAC Community Website This is a free and open site for the dissemination and discussion of issues related to the use of mid-upper-arm circumference (MUAC) including, but not restricted to, case-definitions, surveys, and patient monitoring.
The tape is 25 mm wide. This increases the probability of the table covering the mid point of the upper arm and reduces the effect of over-pulling.
The tape is double sided. One side is for use with children with thresholds marked for moderate and severe wasting and low chest-circumference in neonates). The other side is for adults with thresholds marked for moderate and severe wasting and for pregnant / lactating women.
The tape is numbered and colour-coded allowing use by community-based volunteers.
The tape can measure MUACs up to about 500 mm. This enables the use of PROBIT estimators for GAM, MAM, and SAM in surveys of nutritional status in adults.