Describing the burden of malaria on child development: what should we be measuring and how should we be measuring it?

There are a number of pathways, both direct and indirect, through which malaria infection could impact the course of child development, causing impairment and disability and adding to the burden of malaria. We present an overview of relevant studies that illustrate these pathways, updating the evidence previously presented. We conclude that before the mechanisms and numbers of affected children can be adequately defined, a wider range of potential pathways to impaired development need to be investigated. Only then can the calculation of the burden be evidence-based, rather than merely speculative. Priorities for future research are described. The calculation of the impact of malaria on child development also requires a degree of uniformity in the definition of outcome across studies. This is currently lacking, and suggestions are made for a common approach to the reporting of results.