Agreement between arm circumference, weight for age, and weight for height measures of malnutrition in children.

Agewise agreement between mid-upper arm circumference (AC), weight for age and weight for height assessment of nutritional status was analyzed for 5,509 Indian children 1 to 5 years of age. Sensitivity specificity and positive predictive value of AC are presented. The sensitivity of AC for detecting moderate malnutrition by weight for age or weight for height was found to be low, except in children 13-24 months of age. From 25-58% of the severely malnourished children by weight for age in the age group 25-60 months were misclassified as normal by AC. Specificity of AC was high across the age range indicating that most of the children identified as not malnourished by weight for age or weight for height also had normal AC. The positive predictive value of AC was low for severe malnutrition but high for moderate to mild malnutrition compared to weight for age and weight for height. The findings indicate that AC is not constant over the age range 1 to 5 years, and use of fixed cut-off points for assessing malnutrition from 1 to 5 years is inappropriate. Sensitivity of AC using a fixed-cut-off point clearly decreases with age, and specificity increases with age. Where possible, weight of children is preferable to AC for nutritional status assessment, due to large number of moderately or severely malnourished children likely to be wrongly classified as normal by AC.