The value of DALY life: problems with ethics and validity of disability adjusted life years.

Disability adjusted life years (DAL Ys) have been launched by the World Bank and backed by the World Health Organisation as a measure of the global burden of disease. 1.2 The aim is ambitious: 'The burden of disease has yet to entirely replace traditional approaches to the assessment of health needs as an influence on political decision making. ' 3 Just like quality adjusted life years (QALYs), DALYs combine information about morbidity and mortality in numbers of health years lost. In the DALY approach, each state of health is assigned a disability weighting on a scale from zero (perfect health) to one (death) by an expert panel. 2 To calculate the burden of a certain disease, the disability weighting is multiplied by the number of years lived in that health state and is added to the number of years lost due to that disease (Figure 1 ) . Future burdens are discounted at a rate of 3% per year, and the value of the lifetime is weighted so that years of life in childhood and old age are counted less .