Where I live, the test seems to be more extensive than many other places. I did the WAIS, which is a test that measures all types of thinking, took ages... Also I had an interview as to my life as now, I also included childhood stuff because I do remember it well. They also wanted someone that knew me as a child to participate, but I refused. Also they watched how I did things and at what speed.

In some places they simply guess.

And everything inbetween.