IQ score is your "mental age" (which is figured out by taking your raw IQ test score and then referencing the IQ test table), divided by your actual age, multiplied by 100. So it shouldn't change over time, because as you're getting older to score more correct, the total number is also being divided by a higher number anyway. Because of this, an IQ score can only really be compared to others of the same age.
68% of the population is within 30 points of 100, 85-115, which is one standard deviation. 95% of the population is within 30 points (two standard deviations) of 100, 70-130.
Anyone who claims to have scored over 130 is likely lying, especially if they're posting on escapistmagazine's forums.
Only 4% of the world's population has a score that's three standard deviations out, that's 130-145, or on the other end, 55-70, and then four standard deviations from the norm (0-55, 145+) is the territory of only 1% of the population. A quick google search tells me that the highest IQ on record is 210, and it belongs to physicist Kim Ung-Yong.
tl;dr because of the way IQ tests and standard deviation statistics work, it's a fair to doubt people who claim to be above 115, and that almost everyone who claims to be above 130 is lying. Also you can only compare IQ tests to people your age.
I guess at this point I have to claim that I took an IQ test and my score is 153, but then make a modesty claim that they probably don't mean anything anyway, yeah?
edit: typos, oops. Even people with "IQ's" of 153 slip up occasionally
