Prognostic value of different anthropometric indices over different measurement intervals to predict mortality in 6-59-month-old children.

OBJECTIVE: To compare the prognostic value of mid-upper arm circumference (MUAC), weight-for-height z-score (WHZ) and weight-for-age z-score (WAZ) for predicting death over periods of one, three and six months follow-up in children.

DESIGN: Pooled analysis of 12 prospective studies examining survival after anthropometric assessment. Sensitivity and false-positive ratios to predict death within one, three and six months were compared for three individual anthropometric indices and their combinations.

SETTING: Community-based, prospective studies from 12 countries in Africa and Asia.

PARTICIPANTS: Children aged 6-59 months living in the study areas.

RESULTS: For all anthropometric indices, the receiver operating characteristic curves were higher for shorter than for longer durations of follow-up. Sensitivity was higher for death with one month follow-up compared to six months by 49% (95% CI: 30-69%) for MUAC 115 mm (p0.001), 48% (95%CI: 9.4-87%) for WHZ -3 (p0.01) and 28% (95%CI: 7.6-42%) for WAZ -3 (p0.005). This was accompanied by an increase in false-positives of only 3% or less. For all durations of follow-up, WAZ -3 identified more children who died and were not identified by WHZ -3 or by MUAC 115 mm, 120 mm or 125 mm but the use of WAZ -3 led to an increased false-positive ratio up to 16.4% (95%CI: 12.0-20.9%) compared to 3.5% (0.4-6.5%) for MUAC 115 mm alone.

CONCLUSIONS: Frequent anthropometric measurements significantly improve the identification of malnourished children with a high risk of death without markedly increasing false-positives. Combining two indices increases sensitivity but also increases false-positives among children meeting case definitions.