Grading standard of visual disability.

Cited from Documentation of the Second China National Sample Survey on Disability, 2007.Notes: (1) Blindness or low vision refers to both eyes. In the event that the degree of the two eyes were different, only the eye with better vision was considered. If a person had one eye that was considered to be blind or to have low vision but the other eye was not recognized as visually disabled (greater than 0.3), then that person was excluded from this analysis. (2) The optimum corrected vision referred to the best vision after appropriate eyeglass rectification or vision measured by pinhole glass. (3) Persons with field of vision less than 10 degrees were recognized as visually disabled.