Recently, I’ve witnessed an ever-increasing number of condition-specific utility measures being developed. Much work is being carried out by The University of Sheffield on measures such as the AQL-5D for asthma, and the EORTC-8D for cancer. I struggle to see their use.
Why do they exist?
It’s fair to say that generic preference-based measures of health aren’t always appropriate. For this reason condition-specific measures are used, which might be more sensitive or responsive to different health states within this condition. The problem arises when we want to compare interventions using these measures, which are not comparable with each other. Many have therefore elicited preference weights from the health states defined by these measures to allow the generation of a utility value…
Apples and oranges?
But surely these values are not comparable with QALYs generated using measures such as the EQ-5D or SF-6D, so what’s the point? To be comparable, condition-specific preference-based utilities must represent the same thing as generic utilities, but how can this be? It seems to me that they represent asthma-, cancer- or dementia-related quality of life, not health generally. For this reason I do not see their purpose. They may be of interest at a condition-specific level, but in this case it would surely not be meaningful to elicit preferences from a general population.
Condition-specific measures often need to be compared alongside generic measures, this is certain. However, I fail to see the benefit of eliciting preferences for condition-specific measures over the alternative method of mapping values from a condition-specific measure to a generic measure. It seems to me that this movement risks a regression back to a time when interventions for two different health concerns were not comparable in terms of cost-effectiveness.
Am I missing the point of such measures? Have you used them? What are the advantages and disadvantages of these measures?