While General Intelligence and IQ are commonly used terms in academia, clinical psychology and in day-to-day conversations, it is more common to talk about General Mental Ability (GMA) in organizational and industrial psychology.
Our understanding is that the different terminology is not due to IQ and GMA being different theoretical constructs, nor that the measurements are different in nature. Rather, it’s due to the fact that the goal of measurement is different. While IQ tests aim to produce a score that describes individuals’ intelligence in relation to the general population, GMA tests are mainly used for ranking candidates in recruitment settings. The reference population is therefore more narrow, focusing only on the working population for example, and the position of individuals along the ability scale is shifted.
A consequence of the different goals of measurement is that many individuals get a lower score on a GMA test than on an IQ test. This makes some sense, since it is often of interest to differentiate between individuals that are in the higher ranges of ability in recruitment settings. Therefore, the tasks will be more difficult and the scale won’t cover the very lowest ability range. This will of course depend on the test in question, the quality of the tasks, the method for calculating scores, the data collected during test development among other things.
Another consequence is the frequent use of norm groups in tests used for recruitment. Instead of committing to build a single scale that accurately reflects the population of interest, many test publishers resort to providing many different scales and leaving the choice of reference group (or norm) to the test administrator. In our view, this has caused a lot of confusion regarding the meaning of scores in GMA tests. Our ambition is to provide one well designed and properly calibrated scale, and allow for comparisons to very specific reference groups such as other candidates in a process using the same scale.