Anthropometric surrogates to identify low birth weight babies: hospital based cross-sectional study

ABSTRACT

Background: Birth weight acts as a crucial sensitive and reliable tool to prevent infant and child morbidity and mortality. There has been a considerable interest in recent years for using simple anthropometric measures as an alternative to birth weight. Objective of the study is to determine the cut off values of the anthropometric measurements and to assess the accuracy of the anthropometric surrogates to identify low birth weight babiesMethods: This is a cross sectional study conducted for a period of one year from 1st Dec 2011 to 31st Nov 2012 at Christian fellowship hospital, Oddanchatram, Dindigal, Tamilnadu. Study population included all the live newborns of term gestation at the hospital. A total of 500 newborns were included in the study during the period. Birth weight of the newborn was measured using spring scale to the nearest 25 grams. Head circumference, Chest circumference, Mid Upper Arm Circumference, Foot Length, Thigh circumference, Calf circumference, Crown-hell length were measured using proper guidelines to the nearest 0.1 cm.Results: In the present study, low birth weight was present in 262 (52.4%) of the newborns. Thigh circumference with cut off value of 15 cm had higher sensitivity and specificity of 97.5% and 80.9% respectively. It was followed by Mid upper arm circumference with cut off value of 10 cm, sensitivity of 81.5% and specificity of 93.9%. Thigh circumference and mid upper arm circumference had high area under curve of 0.949 and 0.855 respectively. All the anthropometric measurements were statistically significant at 5% level of significance.Conclusions: Thigh circumference with a cut off of 15 cm, followed by mid upper arm circumference of 10 cm were the better surrogate anthropometric measurements with better sensitivity, specificity to identify low birth weight babies.