Aims of the Global Burden Disease studies

According to Murray et al. (2012), “the Global Burden of Diseases, Injuries, and Risk Factors (GBD) enterprise is a systematic, scientific effort to quantify the comparative magnitude of health loss due to diseases, injuries, and risk factors by age, sex, and geography for specific points in time”.  It assesses the importance of different diseases or risk factors by dividing up the total disease burden between them in order to inform health policy and identify priorities for the allocation of resources.

One impetus to the initial GBD study was the proliferation of competing and incompatible estimates of the health impact of different diseases that impeded the setting of health priorities until the 1990s. Specialists in particular diseases, who want to see resources directed into intervention or research programmes addressing that disease, tend to make pessimistic estimates of the size of the disease burden that results from “their” disease, on the one hand, and optimistic claims about the likely benefits of research into it and interventions against it, on the other.

The competing claims of experts focused on different diseases are difficult to arbitrate between. One reason for this is that the empirical data available on mortality and morbidity by cause across the globe are limited and defective. In addition, individuals often suffer from multiple diseases, several of which may contribute to their poor health or death. For example, a malnourished child who suffers multiple bouts of malaria before contracting measles and dying of pneumonia might be claimed by several disease-specific lobbies as a death from “their” disease. Thus, it is possible to produce widely varying estimates of the health impact of a particular disease or intervention, all of which are scientifically defensible.