A study by the Federal University of Pelotas (UFPel) compared the trends of socioeconomic inequality in the occurrence of child malnutrition in Latin American and Caribbean countries, according to the income differences of the population classified in five and ten economic groups. The research is the result of a dissertation work developed in the Post Graduate Program in Epidemiology of UFPel by nutritionist María de Pilar Flores Quispe, under the guidance of professor Fernando César Wehrmeister and researcher Maria Clara Restrepo Mendez, both of the International Center for Equity In Health of UFPel.

The group analyzed the occurrence of chronic childhood malnutrition in relation to family income in ten countries: Bolivia, Belize, Colombia, Dominican Republic, Guatemala, Haiti, Honduras, Nicaragua, Peru and Suriname, based on national household data from Demography and Health Survey (DHS) and Multiple Indicator Grouping Survey (MICS). Data collection was performed at intervals of three to five years from the mid - 1980s to the mid - 1990s.

The prevalence of chronic childhood malnutrition was defined as the percentage of children under five years old who presented two low standard deviations from the median Z-score height-for-age, according to the World Health Organization (WHO) standard curve for child growth. To assess the impact of socioeconomic inequality, the researchers ranked the sample in five and ten income groups, comparing the differences in child malnutrition in the poorest 10% and 20% as opposed to the richest 10% and 20%.

The results show that eight out of ten countries had a reduction in the national estimate of chronic child malnutrition. Despite the improvement in the indices, the authors warn that the prevalence of chronic malnutrition is greater than 10% in all countries, with the exception of the Dominican Republic, with 6.9%, and Suriname, with 8.8%. In Guatemala, for example, almost half of the children are undernourished. When evaluated by decile, among the poorest, prevalence fell by one percentage point in countries like Colombia (-0.6), Dominican Republic (-1.0), Haiti (-0.9), Honduras (-1.0) and Peru (-0.7 ).

According to the analysis, the poorest 10% still have a higher prevalence of chronic childhood malnutrition than the poorest 20%, with a difference of 30% in Belize and 20% in the Dominican Republic, between groups. In relation to the impact of economic inequalities on child malnutrition, Colombia, Belize, Suriname, and the Dominican Republic have the best performance in reducing absolute and relative inequalities between rich and poor, while Bolivia and Guatemala have increased these differences, with the worst scenario regarding evolution of inequalities.

"Most of the previous studies use the income quintile classification to assess inequalities in child malnutrition. Our study uses the classification in decile of income to identify more pronounced differences between the socioeconomic subgroups and to emphasize the urgent need to reach the most vulnerable subgroups ", explains the author of the study.

In the case of Belize, the difference in prevalence of malnutrition was 47 percentage points among the poorest 10% and the richest 10%, and 31% among the poorest 20% and 20% richest in 2006. In 2011, these differences were 14 percentage points in the comparison between deciles and only seven percentage points in the comparison between quintiles.

"In this example, the evaluation by deciles shows twice the difference between extreme income groups compared to quintiles, which would go unnoticed in an analysis based only on income quintiles," concludes the author.