Relationship between the surrogate anthropometric measures, foot length and chest circumference and birth weight among newborns of Sarlahi, Nepal.
BACKGROUND
Classification of infants into low birth weight (LBW, <2500 g) or very low birth weight (VLBW, <2000 g) categories is a crucial step in targeting interventions to high-risk infants.


OBJECTIVE
To compare the validity of chest circumference and foot length as surrogate anthropometric measures for the identification of LBW and VLBW infants.


METHODS
Newborn infants (n=1640) born between March and June 2004 in 30 Village Development Committees of Sarlahi district, Nepal.


METHODS
Chest circumference, foot length and weight (SECA 727, precise to 2 g) of newborns were measured within 72 h after birth. The sensitivity, specificity and predictive values for a range of cutoff points of the anthropometric measures were estimated using the digital scale measurements as the gold standard.


RESULTS
Among LBW infants (469/1640, 28.6%), chest circumference measures <30.3 cm were 91% sensitive and 83% specific. Similar levels of sensitivity for foot length were achieved only with considerable loss of specificity (<45%). Foot length measurements <6.9 cm were 88% sensitive and 86% specific for the identification of VLBW infants.


CONCLUSIONS
Chest circumference was superior to foot length in classification of infants into birth weight categories. For the identification of VLBW infants, foot length performed well, and may be preferable to chest circumference, as the former measure does not require removal of infant swaddling clothes. In the absence of more precise direct measures of birth weight, chest circumference is recommended over foot length for the identification of LBW infants.
Mullany
L C
LC
Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD 21205-2103, USA. lmullany@jhsph.edu
Darmstadt
G L
GL
Khatry
S K
SK
Leclerq
S C
SC
Tielsch
J M
JM
D000886:Anthropometry / Q000379:methods*; D001724:Birth Weight / Q000502:physiology*; D003906:Developing Countries; D005260:Female; D005528:Foot / Q000033:anatomy & histology*; D006801:Humans; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D008297:Male; D009390:Nepal; D011237:Predictive Value of Tests; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013909:Thorax / Q000033:anatomy & histology*