A CBA of corrective lenses, including the benefits for reducing the symptoms of dementia

Abstract

We carried out a CBA of corrective lenses (CLs) that had direct benefits, and included indirect benefits working through a reduction in dementia symptoms. The benefits took the form of a reduction in mortality that was expressed in monetary terms by using the value of a statistical life (VSL) methodology. The indirect benefits consisted of CLs first lowering dementia symptoms and in this way reducing mortality. Estimation of the impact on mortality of CLs and dementia symptoms was carried out using a random effects Logit regression on a large national panel data set provided by the National Alzheimer’s Coordinating Centre. The effect of CLs on dementia symptoms was estimated by a fixed effects regression. The VSL figure came from the literature. The net-benefits overall were positive and large, and even positive just from the indirect dementia benefits alone.