Utility analysis tells all
- Correspondence to: Melissa Brown Center for Value-Based Medicine, PO Box 335 Flourtown, PA 19031-1404, USA; mbrownvaluebasedmedicine.com
We must embrace it and foster its use
It is most gratifying to see the excellent article by Gupta et al in this issue of BJO (p 1241), as advocates of preference based quality of life instruments such as utility analysis (those that ask patients to make a choice about the desirability of their quality of life) versus function based instruments (those that measure primarily function: physical, psychological, vocational, avocational, cognitive, social, and so forth).1
Why are we such fans of utility analysis? The answer lies in the definition of what is the most desirable quality of life instrument.1 A good instrument should be:
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all encompassing with regard to the variables that comprise quality of life
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sensitive to small changes in health
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reliable (reproducible)
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applicable across all medical specialties
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able to be completed within a reasonable time period
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able to be understood by patients, and
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able to demonstrate construct validity (the ability to measure what it is intended to measure
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applicable for us in performing healthcare economic analyses.
Utility analysis meets all of these parameters and is a major pillar of value based medicine, the practice of medicine that incorporates the best evidence based data with patient preferences to assess the value conferred by our interventions, whether medical, surgical, and/or pharmaceutical. Of special note as well is the fact that these patient derived utility values that measure the quality of life associated with health states appear to be innate to human nature. How do we know? Because data2,3 suggest that, for the most part, utility values transcend sex, ethnicity, age, level of education, income, and even nationality, There are, of course, exceptions, such as this analysis found with education, but overall human attitudes towards illness are remarkably similar.
Utility analysis incorporates improvements in quality of life conferred by interventions that can be integrated with improvement in length of life to quantify the total value gained from the interventions. This value (measured using the QALY, or quality adjusted life year) is comparable across every intervention in health care. The most frequently utilised quality of life instruments in ophthalmology, the VF-14 and the NEI-VFQ-25, are not especially applicable across all specialties and have not been used in healthcare economic analyses.
As policy makers and other stakeholders in health care utilise quality of life data to make allocation decisions, it seems natural that they would favour an instrument than encompasses all interventions in health care, rather than just ophthalmology, which accounts for a small fraction of the healthcare dollar.1
How should we, as ophthalmologists, approach the introduction of value based medicine? With open arms. The great majority of ophthalmic interventions confer extraordinary value, and it is value that patients want. An added benefit is that the conferred value is great compared to the costs expended. Cataract surgery in the United States costs $600–$700/QALY. It is a bargain by any measure.
