COHA is based on a model that was originally developed in Latin America by the Economic Commission for Latin America and the Caribbean (ECLAC). The conceptual framework was adapted to the African context with the support of experts and representatives from the national implementation teams of the participating countries. The process of adaptation was carried out in partnership with ECLAC and was endorsed by the African Task Force on Food and Nutrition Development (ATFFND).
This framework establishes clear linkages between the direct consequences of undernutrition, taking into account the particular structures of the labour market on the continent, as well as the limitations in available data. The result allows the model to clearly define boundaries in the cost analysis, both from a public and individual perspectives, as well as to define a clear differentiation between direct costs and opportunity costs in the results.
The COHA model is used to estimate the additional cases of morbidities, mortalities, school repetitions, school dropouts and reduced physical capacity that can be directly associated to a person's undernutrition before the age of 5. Using these risk factors, alongside economic, demographic, nutritional, health and educational data provided by each country team, the model then estimates the associated economic losses incurred by the economy in health, education and potential productivity in a single year.
The COHA model utilizes a two-dimensional analysis to estimate the costs arising from the consequences of child undernutrition in health, education and productivity. The incidental retrospective dimension analyses the history of child undernutrition in the country in order to estimate the current economic and social consequences. To complement this analysis, a prospective dimension is used to project and generate scenarios for analysis.