Objective: The present study aimed to evaluate the clustering of undernutrition indicators of children under the age of 5 years in relation to different scales. Design: A community-based cross-sectional study design was employed. We collected anthropometric data, geographic locations/elevations of households and other data from visited households. We used a retrospective purely spatial Poisson probability model to identify and locate clusters (high rates) of stunting and wasting using the software SaTScan™ version 9·1·1. We ran a logistic regression model to help evaluate the causes of clustering. Settings: Six villages in the Meskane Mareko District (38·45763°E, 8·042144°N) of southern Ethiopia. Subjects: We surveyed 2371 children aged <5 years, who were found in 1744 households. Results: We found a micro-level variation in the risk of stunting and wasting within the studied district. We found the most likely significant clusters for wasting and severe wasting in two of the six villages. For stunting, a single large cluster size of 390 cases (304·19 expected) in 756 households was identified (relative risk = 1·48, P < 0·01). For severe stunting, a single cluster size of 106 cases (69·39 expected) in 364 households was identified (relative risk = 1·69, P = 0·035). Conclusions: We conclude that the distribution of wasting and stunting was partly spatially structured. We identified distinct areas within and between villages that have a higher risk than the underlying at-risk population. Our analysis identified the spatial locations of high-risk areas for stunting that could be an input for geographically targeting and optimizing nutritional interventions.
KeywordsClustering Undernutrition Stunting Wasting EthiopiaThe burden of undernutrition has declined progressively in developing countries, with the rate of reduction varying by region. The largest reductions have been in Asia, whereas a modest reduction in prevalence is documented in Africa (1) . Ethiopia has documented a significant decline in the prevalence of both stunting and underweight over the past 14 years (between 2000 and 2014). For example, the prevalence of stunting decreased by 31 % (from 58 % to 40 %), while the prevalence of underweight decreased by 39 % (from 41 % to 25 %), between 2000 and 2014 (2-5) .Although this is significant progress in the reduction of stunting and underweight prevalence, the current prevalence levels are still considerable. Based on the WHO recommended criteria for assessing the severity of stunting and underweight at the population level, the country is classified under a medium to high grade (prevalence range of 20-40 % for stunting and 10-30 % for underweight). To help ameliorate the current unacceptably high burden of undernutrition among children under the age of 5 years, the Government of Ethiopia has launched a national nutrition programme (June 2013-June 2015 prioritizing nutrition as a viable strategy for the country's growth and development plans (6) . Among other things, a reduction in the burden of ch...