Limitations of IQ testing.

What does IQ actually measure? What does IQ fail to measure? How much more intelligent is someone who scores 70 (for example) than someone who scores 75? It is very easy to invest a lot of meaning in a simple number reflecting a person’s IQ – but it is important to bear in mind that it is in fact a score calculated from a person’s responses to a series of questions and tasks in a testing environment – not an analysis of how they perform in real life.  A number of things can influence how a person performs on IQ testing – motivation, ability, alertness, level of comfort, concentration level, prior exposure/familiarity, and so on. Many of these can vary significantly over time and people do not get exactly the same score when they are given the same test several times. In addition, different tasks in the IQ test require different skills. Some people may be very good at some tasks but not at others, although the full-scale IQ score will not indicate this as it lumps all the test results together.  For this reason, the person administering the IQ test often provides an interpretation or understanding of the actual test results and it is important to consider this in relation to the actual score to be able to understand this.