An intelligence quotient (IQ) is a total score derived from a set of standardized tests or subtests designed to assess human intelligence. Originally, An intelligence quotient (IQ) is a total score derived from a set of standardized tests or subtests designed to assess human intelligence. Originally, IQ was a quotient obtained by dividing a person's estimated mental age, obtained by administering an intelligence test, by the person's chronological age. The resulting fraction was multiplied by 100 to obtain the IQ score. For modern IQ tests, the An… With the advent of the concept of g or general intelligence, many researchers have found that there are no significant sex differences in average IQ, though ability in particular types of intelligence does vary. Thus, while some test batteries show slightly greater intelligence in males, others show greater intelligence in females. In particular, studies have shown female subjects performing better on tasks related to verbal ability, and males performing better on tasks related to rotation of objects in space, often categorized as spatial ability. These differences remain, as Hunt (2011) observes, "even though men and women are essentially equal in general intelligence". Some research indicates that male advantages on some cognitive tests are minimized when controlling for socioeconomic factors. Other research has concluded that there is slightly larger variability in male scores in certain areas compared to female scores, which results in slightly more males than females in the top and bottom of the IQ distribution. The existence of differences between male and female performance on math-related tests is contested, and a meta-analysis focusing on average gender differences in math performance found nearly identical performance for boys and girls. Most IQ tests, including popular batteries such as the WAIS and the WISC-R, are constructed so that there are no overall score differences between females and males.

Generational changes of intelligence test performance in the general population (the Flynn effect) have been observed all over the world since the early 1940s. These changes are known to be country- and intelligence test domain-specific. To investigate whether such IQ gains are observable in three distinct domains of intelligence (verbal reasoning, spatial ability, mathematical reasoning) in German-speaking individuals, we examined a mixed-sex sample of 449 university students in a cross-sectional design. We assessed students’ IQs on three original (standardized in 1970) and revised subscales (standardized in 2000) of a widely used German intelligence test battery, thus allowing investigation of test score changes over a time span of 30 years. Participants scored significantly higher on all subscales of the original test. Additionally, we observed higher performance of men than of women on all subscales, but only little evidence for sex differences regarding test score gains. In all, the Flynn effect appears to be progressive, robust, largely sex-independent, and intelligence domain-specific in respect to the magnitude of gains in German-speaking individuals.