Carl Abraham

Many people think vision is an all-or-nothing experience; you either see or you don’t. In reality, vision exists on a continuum. Between perfect sight and total blindness are many levels of visual ability, and this is where low vision lies. Visual impairment is the general term used for people whose vision is less than normal, with normal vision measured as 6/6 or 20/20. For many, spectacles, contact lenses, or surgery can restore vision to this level.

CONFLICT OF INTEREST STATEMENT The authors declare no conflict of interest. Supporting Information Filename Description opo13268-sup-0001-TablesS1-S3.docxWord 2007 document , 51.7 KB Tables S1–S3. REFERENCES 1, , , , , , et al. The association of health-related quality of life with severity of visual impairment among people aged 40–64 years: findings from the 2006–2010 behavioral risk factor surveillance system. Ophthalmic Epidemiol. 2016; 23: 145–153. 2, .