Mid-arm circumference: an alternative measure for screening low birth weight babies

Birth weight is a reliable and sensitive indicator for predicting the immediate or later outcome of a newborn child. In a developing country like Bangladesh, where more than 75% of deliveries occur in rural community and are mostly attended by Traditional Birth Attendants (TBA) or relatives, birth weight cannot be recorded mainly due to paucity of suitable weighing scale. To overcome the problem associated with weighing the newborn, it was considered justified to find out other simpler measurements that could be used as substitute of weighing, in order to identify low birth weight babies. A cross sectional, analytical, hospital based study was conducted at Dhaka city on 560 newborn babies born during a period of 18 months in 2000-2001 to examine relative validity of mid-arm circumference as a screening measure of low birth weight babies. Mid-arm circumference, length, head circumference, chest circumference, abdominal girth, and calf circumference were considered. The study showed a strong correlation (p < 0.001) between mid-arm circumference (r = 0.956) and birth weight, followed by calf circumference (r = 0.946) and birth weight. Other parameters were also strongly correlated (p < 0.001). The study showed that in identifying newborns of <2500 gm a mid-arm circumference of <9 cm had the best sensitivity (96.2%) and specificity (97.3%). A value of <8 cm and <6.8 cm for mid-arm circumference showed highest validity for picking up newborns weighing <2000 gm and <1500 gm respectively. Measurement of arm circumference is easier, convenient and statistically superior to other anthropometrical parameters in this work. The researchers recommend designing of simple 'Tri-colored tape' for early detection of 'At Risk' newborns in rural community for their timely management.