Indicators of Disability Burden: QALYs/DALYs

With the growing demand for health services, the question of allocating limited resources between alternative public programmes of differing objectives is of much concern to economic planners. An objective way of making such decisions is to rely on the economic efficiency of programmes. For this, quantitative indicators bringing out an assessment of disease burdens and the benefits realised due to medical interventions are needed. The quality adjusted life years (QALYs) and the disability adjusted life years (DALYs) are two such measures which have become popular recently.

Quality of life is a commonly used concept but has no universally accepted definition. It can be interpreted as the degree to which persons perceive themselves able to function physically, emotionally, and socially. In a general sense, it is the state of well being which makes life worth living. In a quantitative sense, it is an estimate of remaining years of life free of impairment, disability, or handicap. Quality of life has been measured in a number of different ways, ranging from more complex, multidimensional scales such as the SF-36 (8 subscales) to very simple, one-item instruments such as the Excellent/Very Good/Good/Fair/Poor (EVGGFP) measure. The latter measure, seemingly simple, has been found to carry high reliability and validity. Quality of life can be measured at a single point in time or over a period of time using measures like QALYs/DALYs.