Abstract
Purpose::
The US panel on cost-effectiveness and NICE in the UK have recommended that health outcomes in cost utility analyses should be weighted by the preferences of society and not patients. However, existing societal-based preference measures either do not include items on vision loss or include a limited assessment of visual functioning. Moreover, published info on the extent by which members of society with good vision judge the impact of vision loss on quality of life is limited. The objective of this research is to develop methods for capturing societal-based utility preferences regarding the impact of ophthalmic disease.
Methods::
The 25-item NEI-VFQ (VFQ) will be simplified via principal components analysis and item response theory using data from both observational and clinical studies. Exploratory item reduction will be stratified by peripheral versus central vision loss and via a pooled sample. Creation of visual functioning health states from the reduced items will include clinician review and patient interviews. Health utility valuations based on the health states will be collected from the public in Australia, Canada, UK, and US.
Results::
The need for such a utility measure for ophthalmic conditions and the development process will be described, and will include the pros and cons of alternative approaches to obtaining utility data. The simplified VFQ based on analysis of >3,500 unique patients with glaucoma, DME, RVO, uveitis, or ARMD will be presented, along with the methodology for utility elicitation from 800 members of the general public (n=200 per country).
Conclusions::
With limitations of existing utility measurement for ophthalmic conditions, a new utility measure based on the VFQ will provide necessary information for cost-utility analyses that are required by various health care payers and regulatory agencies.
Keywords: quality of life • clinical (human) or epidemiologic studies: biostatistics/epidemiology methodology