How Psychologists Manage IQ Tests

People have been getting smarter for 100 years, according to IQ tests

Vienna - intelligence tests are anything but undisputed. Because the common intelligence quotient - normalized to the average target performance of 100 points - is only based on certain skills. Many psychologists and neuroscientists consider this level of intelligence to be insufficiently differentiated to really grasp the complex phenomenon. In addition, the determined IQ is subject to strong fluctuations during puberty, for example.

Nevertheless, the values ‚Äč‚Äčachieved in IQ tests are considered an indication of how intelligent a person is. The tests are constantly being adapted and improved. In addition, the results have steadily improved over time, as the psychologists Jakob Pietschnig and Martin Voracek from the University of Vienna report in the journal "Perspectives on Psychological Science":

Using data from nearly four million people from 31 countries, they observed increases of around three IQ points worldwide per decade over a period from 1909 to 2013. These increases were evident in both reasoning and, although to a lesser extent, knowledge.

Explanation for the "Flynn Effect"

The Viennese researchers were not the first to observe this phenomenon in a so-called meta-analysis. Since the first systematic description of IQ test performance gains in the general population in the United States more than 30 years ago, this phenomenon has preoccupied intelligence researchers around the world. The causes and the course of this phenomenon, now known as the "Flynn effect", are of course controversial among scientists: Generally, better nutrition and better education are held responsible for it.

The Viennese researchers have a slightly different explanation: the observed increases in IQ do not seem to represent global increases in cognitive performance, but rather an expression of greater skill specialization and better test processing strategies of participants. In addition, the growth does not appear to be linear. During the Second World War they were very low. And although the increases are still ongoing, the study results show a massive decrease in IQ increases over the past few decades. (tasch, 1.6.2015)