Myopia has emerged as a major health issue in east Asia, because of its increasingly high prevalence in the past few decades (now 80-90% in school-leavers), and because of the sight-threatening pathologies associated with high myopia, which now aff ects 10-20% of those completing secondary schooling in this part of the world. Similar, but less marked, changes are occurring in other parts of the world. The higher prevalence of myopia in east Asian cities seems to be associated with increasing educational pressures, combined with life-style changes, which have reduced the time children spend outside.

Myopia has emerged as a major health issue in east Asia, because of its increasingly high prevalence in the past few decades (now 80-90% in school-leavers), and because of the sight-threatening pathologies associated with high myopia, which now aff ects 10-20% of those completing secondary schooling in this part of the world. Similar, but less marked, changes are occurring in other parts of the world. The higher prevalence of myopia in east Asian cities seems to be associated with increasing educational pressures, combined with life-style changes, which have reduced the time children spend outside.

In this trial, the investigators aim to study the evolutionary model of myopia in China, which could provide new insight into the social development and human adaptation.

Inclusion Criteria:

• Patients complete the examination of Refractive error from 2005 to 2015 year.

Exclusion Criteria:

• Patients could not complete the examination of Refractive error

Subjects from all the province of China who undergoing the examination of Refractive error from 2005 to 2015 year.