Measuring the Global Burden of Disease: Epic Measures
A book about the measurement of Disability Adjusted Life-Years (DALY) and the Global Burden of Disease
Calculating the global burden of disease – a measure of what ails and kills whom, everywhere, is no small feat. Epic Measures is the story of Chris Murray and colleagues developed the DALY and measured the global burden of disease through 20 years of hard work.
How could this possibly be interesting? It's definitely interesting! The story focuses on the personal and political struggle to achieve a global burden of disease measurement – against bureaucratic inertia at the WHO and other UN agencies, and resistance and competition from other academics and sector experts. Murray’s fearless and righteous drive is impressive and inspiring (and intimidating). The accounts of the infighting between different agencies – including the Lancet and other key publications – is fascinating and, at once, disappointing. It really highlights the point (made by Richard Horton) that “Good science is polarizing, from Galileo to Chris Murray”. But it also highlights the importance of communication of research findings.
After the first global burden of disease measurement effort - the World Development Report in 1993 - this project became highly mobile. Controversy pushed the effort from the WHO, to the World Bank, to Harvard, and finally developing the Institute of Health Metrics and Evaluation at the University of Washington in Seattle (with funding from BMGF). The next Global Burden of Disease Study was launched in 2012 in a special edition of the Lancet.
What did the measure tell us? It emphasized gains have been made in combatting maternal, child and communicable disease mortality in low and middle income countries between 1990 and 2010. However, as life expectancy increases, the same non-communicable conditions that people suffer in rich countries – heart disease, diabetes and stroke became the top killers (see mortality data visualization). It also highlighted depression, anxiety and neck-pain as being huge causes of morbidity – and that these morbidity patterns are fairly consistent the world over.
So it’s a lot of stats? The book does not explain the methodology, which I found disappointing – it could have at least been included in an appendix. The people who are likely to buy the book will want at least a cursory understanding of the stats and data sources – the market is probably quite specific (no-one is tossing up between buying this book and the next George RR Martin). For methodological details, you need to go to the website: see: http://vizhub.healthdata.org/mortality/
Did the measure change anything? Countries that have embraced the data and methodology (Australia, Mexico) have restructured their efforts around not just factors which kill people, but also those that cause the most suffering. This makes economic sense: the factors which cause high morbidity, not mortality, are the most expensive for a health system, but until now they have no been visible in the data. It is this DALY data which means that depression now gets so much funding and support in the Australian health system (see for example, Beyond Blue).
What annoyed you about the book? The subtitle: “One Doctor. Seven Billion Patients”. This is not medicine, it’s public health – Chris Murray is a medical doctor, but that has no bearing on this effort. So bored of people confusing medicine and public health – and thinking that doctors – by default – can be public health decision makers (of course they can sit at the table!).
But how will this book change the way you work?
I went straight to the website and played with the data visualization tools – and will keep referring back to these (see: http://www.healthdata.org/results/data-visualizations)
I will now avoid – or at least cross-check – any UN mortality or morbidity estimates – unless I know the exact data source (for example, I think the UNICEF 2009 CES in India is ok).
The book definitely gives you an appreciation of a more comprehensive approach to health systems and planning. The availability of this data enables the shift from vertical programming to a comprehensive systems approach.
Most immediately – for any discussion of an essential package of care offered under universal health coverage – a burden of disease study is the starting point.