According to some studies, the world mean I.Q. score, on the Wechsler Scale, is around 8573,
with countries ranging from the high 50’s to almost72-73 110. Since different countries have
different average I.Q. scores, in order to compare them, the test scores have to be adjusted to the
Greenwich I.Q. standard73 which mean is set at 100.
On the next page, here are a few examples of mean I.Q. scores by country in 2020-202172:
For simplicity’s sake, suppose you are British, and your I.Q. score is 100 (in the U.K. the mean is 100).
If you are travelling to Greece (where the mean is 92) then it’s as if your I.Q. score had been measured as 108
there, putting you in the Upper Normal range (I.Q. 100-114) of the Greek intellectual sphere.
Likewise, if you are vacationing in Japan (where the mean is 105) there, your I.Q. score will only be equivalent to
95, so in the Lower Normal range (I.Q. 85-99).
