Nearsightedness (myopia) is variously extended in the world, but there are considerable differences between ethnic and racial groups because hereditary factors play the central role. In the Western Europe and in the USA there is about 25% of individuals aged 12-54 years, who are shortsighted.

Naturally, there are significant variations depending on the composition and the age of groups (e.g. greater extension of myopia among university students and intellectuals).

Myopia increases from the Western Europe through Eastern Europe to the Orient with the maximum in the Far East. Japan has the highest amounts, up to 60-70% of myopia in population (undergraduates up to 80%). The Orient has a similar high extension, especially of severe myopia with possible serious complications.