Newborn Mid–Upper Arm Circumference Identifies Low–Birth Weight and Vulnerable Infants: A Secondary Analysis

Low birth weight (LBW) infants are at increased risk of morbidity and mortality. Identification of LBW may not occur in settings where access to reliable scales is limited. Mid–upper arm circumference (MUAC) may be an accessible, low-cost measure to identify LBW and vulnerable infants. We explored the validity of newborn MUAC in identifying LBW and vulnerable newborns in rural Sierra Leone. This study was a secondary analysis of infant data from a randomized controlled clinical trial of supplementary food and anti-infective therapies compared with standard care for undernourished pregnant women. Data for singleton liveborn infants with birth measurement and 6-mo survival data were included in this analysis. The primary outcome was validity of MUAC in identifying low–birth weight (LBW) neonates. Secondary outcomes included validity of MUAC and head circumference (HC) in identifying weight-for-length z-score (WLZ)