How we are getting better at measuring non-fatal health outcomes – but still struggling
Combining non-fatal health and mortality outcomes into a summary measure of population health was an important new approach pioneered in the first Global Burden of Disease study. It led to, for instance, greater emphasis in health policy considerations given to mental disorders and musculoskeletal disorders.
Estimating disability, however, is a more complicated and time-consuming task than estimation of mortality and years of life lost to premature mortality. For each disease, and often for each sequela, or disability resulting from a disease or injury, the available data on multiple disease parameters need to be collated, analyzed, and checked for consistency. The data come from large numbers of data collections using different methods and are prone to multiple, varying sources of bias. In the past, estimates relied heavily on the informed, or not so informed, choices by a small number of burden researchers. Few of these choices were challenged, as few people knew enough about methods. In the Global Burden of Diseases, Injuries, and Risk Factors 2010 Study (GBD 2010), we researchers set ourselves much greater challenges, such as making use of all available data, quantifying uncertainty, and expanding the causes of death list. We made country estimates for multiple time periods, and by actively involving many more researchers, we have been under much greater scrutiny than ever before.
GBD 2010 has made enormous progress in improving the quality of non-fatal health estimates and getting buy-in from experts around the world. Yet, many unresolved or "under-resolved" issues remain that can be solved with improved data and new approaches, thus setting an exciting agenda to tackle in coming years.
Professor Theo Vos is Director of the Centre for Burden of Disease and Cost-Effectiveness, University of Queensland. The Centre aims to provide health policymakers with the best available evidence to guide the allocation of resources. Dr. Vos has carried out burden of disease studies in Mauritius and Australia and has made major contributions to the studies in Zimbabwe, Thailand, South Africa, Malaysia, Singapore, and Vietnam. The last five years he has been actively involved in the core team of researchers directing an update of the Global Burden of Disease.
Dr. Vos has also led large economic evaluation projects; the two largest were a) the ACE-Prevention project, which evaluated the cost effectiveness of 150 (mostly) preventive interventions in Australia; and b) the SPICE project in Thailand examining intervention options for tuberculosis, mental disorders, lifestyle risk factors and road traffic injuries. He is currently part of a core team of researchers on the Disease Control Priorities Network project, which aims to provide policy advice to assist priority setting in health for low- and middle-income countries.