Acknowledgements

but we believe that the global estimate of 8.2 million blind persons due to un-corrected refractive error by Resnikoff et al. is an overestimate, largely due to the inclusion of an implausibly high estimate for India. While on the one hand we should not overlook blindness due to uncorrected refractive error as it can be addressed relatively easily, on the other hand we should be careful not to swing the pendulum in the other direction by overestimating it. Related to this issue, we have also published a proposal for revision of the definitions of blindness and visual impairment in the International Statistical Clas-sification of Diseases that would take into account the inclusion of refractive error as a cause of blindness and visual impairment.4