Validity and g-loading of specific tests
While IQ is sometimes treated as an end unto itself, scholarly work on IQ focuses to a large extent on IQ's validity, that is, the degree to which IQ predicts outcomes such as job performance, social pathologies, or academic achievement. Different IQ tests differ in their validity for various outcomes.
Tests also differ in their g-loading, which is the degree to which the test score reflects general mental ability rather than a specific skill or "group factor" such as verbal ability, spatial visualization, or mathematical reasoning). g-loading and validity have been observed to be related in the sense that most IQ tests derive their validity mostly or entirely from the degree to which they measure g (Jensen 1998).