If, for instance, we want to find the burden of bach ache, we must first define what we mean by bach ache. Do we mean an incapacitating condition or do we mean a slight discomfort?

Only when the condition is defined and described will it be meaningful to ask how much this condition reduces the quality of life of the one carrying it.

How much should the value of a life year be adjusted for back ache? The disabilty weighting is the most difficult and controversial part of the DALY approach. We will come back to this.

Here we show how it is currently done.