A study on the sensitive period of visual impairment of primary and middle school students in Guangzhou

Objective To explore the sensitive period of visual impairment of primary and middle school students,and to provide the basis for protecting students' vision and preventing and controlling myopia.Methods The data of monitoring primary and middle school students' health in Guangzhou was used,the results of the eyesight examination of students in the year 1993,2003 and 2013 were selected.And the method of dynamic data analysis was employed to calculate the annual detection rate of poor eyesight of the annual growth rate and its correction value to exceed the annual growth rate of average± 1 s as the sensitive period of visual impairment boundary value.Results The sensitive period of visual impairment of primary and middle school students in Guangzhou was basically in the range of 8 to 16 years old,and the peak of visual impairment differed in different academic year,and the peak periods of visual impairment of the boys in 1993,2003 and 2013 were were 12 to 14 years old,11 to 12 years old,8 to 9 year old,respectively,and those for girls were 11 to 13 years old,9 to 11 years old,8 to 10 years old,respectively.Conclusion There is indeed a sensitive period of visual impairment in primary and middle school students.During the academic year of 1993 to 2013,the sensitive period of students turned up a forward tendency,and younger students tended to have poor eyesight.