Blindness and visual impairment severely impact the visual health and life quality of people, particularly the 2.566 million senior citizens aged at 65 and above in Shanghai. The main reason is uncorrected refractive error, of which, 62.1% can be solved through refractive correction. For this reason, the uncorrected refractive errors of 154,000 senior citizens in Shanghai can be taken as a priority among the public health issues to prevent blindness. Now, with the aim to reduce the prevalence rate of blindness and visual impairment, it is planned to establish a public health service mechanism in terms of refractive error screening and correction for the elderly by relying on Shanghai's three-level (city-district-community) eye diseases prevention network, using proper refractive correction technology, and moving related services forward to communities in order to screen, identity, and correct blindness and visual impairment caused by refractive errors as early as possible.

Inclusion Criteria:

• shanghai residents aged ≥18 years old

Exclusion Criteria:

• cognitive and/or mobility disorders; non-shanghai residents; younger than 18 years old.