There are roughly two types of psychometric testing: the aptitude or ability test and those focused on personality or affinity.
Aptitude tests aim to measure the person’s level of competence or ability in one or more specific areas. The most common tests of this type are those that measure verbal aptitude and intelligence. There are, however, a wide variety of different aptitude tests, depending on the position for which you are evaluating. For example, to evaluate software development professionals, specific tests can be used to measure the applicant’s ability to solve algorithms and other problems through programming. Most aptitude tests are usually time-controlled as the speed of response is usually an important factor. Unlike personality tests, in aptitude tests, there are correct or incorrect answers and it is possible to use them to objectively determine which candidates have the highest levels for the competence or skill sought. For example, identify the candidates with the highest reading comprehension ability. These tests allow not only to “rank” candidates but also to understand what the result obtained by a candidate means. For example, if intelligence is being evaluated, the test should be able to tell whether the candidate has a high, low, or medium level of intelligence. These tests are ideal for pre-filtering candidates, as they are objective and have a great predictive capacity for future performance, but cannot be used as the sole factor for hiring decisions.
On the other hand, the personality or affinity tests do not seek to establish a ranking or determine whether a person is good or bad at something, but to discover attributes of their personality, behavior, and preferences. In general, there are no good or bad answers in this type of tests and one result is no better than another. However, some profiles fit better than others for particular jobs. For example, an extremely creative person who always likes to do new things might be a good candidate for research and development, but perhaps not for purely operational and routine work. Similarly, a team made up exclusively of very introverted people might not be ideal. Another important use for this type of testing is just to ensure a healthy level of diversity to have teams where different kinds of opinions and ideas are given. We said earlier that a very creative person might not be the best fit for an operational job, but maybe if we need a team of 10 people to do operational tasks, it might be interesting to have a creative person who could help with new ideas on how to do the job better.
It is most common to use psychometric pre-filtering aptitude tests and personality tests to get to know the candidate better and to ensure that it is a good fit for the position, team, and culture of the organization.