The earliest forms of testing emerged in China (2200 B.C). There were no tests for validity and reliability, although the tests did incorporate relevant selection criteria.

Physiognomy states that it is possible to judge the inner character of people from their appearance, specifically, the face. This is an early form of psychological testing and gave rise to phrenology, using the bumps on the skull as an indicator of personality.

In the early days of experimental psychology, brass instruments were used to measure sensory thresholds and reaction times while linking this to intelligence. During this time, Wundt measured the speed of thought of individuals.

Galton demonstrated that individual differences exist and are objectively measurable. He also demonstrated that objective tests could be devised and that meaningful scores could be obtained through standardized procedures. Wissler was the first to attempt to validate measurements and demonstrated that the use of reaction time and sensory discrimination for intelligence were severely flawed.

Thomasius was the first to use rating scales and was the first to systematically collect and analyse quantitative data. After his use of rating scales, it was used more often in psychology.

Esquirol was the first to formalize the difference between mental retardation and mental illness in writing. He stated that mental retardation was a lifelong phenomenon, whereas mental illness had a more abrupt onset in adulthood. He also proposed the first classification system in mental retardation mainly focused on language skills. Seguin developed educational programmes for people with mental retardation.

Binet proposed the first intelligence test in 1905 and before that suggested the influence of not using a strict methodology. Binet’s tests were heavily focused on verbal skills. Binet standardized the test and introduced the concept of mental level. This led to the comparison of mental age with chronological age in order to determine intelligence.

TESTING FROM 1900 TO PRESENT
Goddard was an early, influential American psychologist who misused intelligence tests. He applied intelligence tests to immigrants without checking the cultural differences and the differences in translation and did not take the context into account. His intelligence testing was strongly influenced by the social ideologies of his time.

Hollingsworth demonstrated the difference between gifted and highly gifted people and stated that gender differences in eminence and achievement were due to social and cultural impacts.

There was progress in the first world war on group intelligence testing. However, the testing on recruits was not very successful due to the large amount of recruits (1), the difficulty comparing verbal and non-verbal tests (2) and the lack of validation of the test (3). However, it did provide psychologists with a lot of experience in the psychometrics of test construction (1) and practice with statistical techniques (2).

A single aptitude test measures one ability domain and a multiple aptitude test measures several distinct ability areas. The development of aptitude tests lagged behind intelligence tests because of a lack of statistical techniques appropriate for aptitude tests (1) and the absence of practical application for these instruments (2).

After the second world war, Woodworth developed a test to assess who was susceptible to psychoneurosis. The Bernreuter personality inventory was one of the first personality tests. It was innovative, as a single test item could contribute to more than one scale.

The Rorschach test was developed to reveal the inner most workings of the abnormal subject, the Thematic Apperception Test was developed as an instrument to study normal personality. This test included ambiguous interaction and the participant making up a story about it. The underlying personality needs would be revealed by the content of the story according to Murray.           

Projective testing as characterized by Rorschach and the TAT included techniques such as free association, sentence completion and interpretation. Projective tests were mainly used to assess (ab)normal personality.

Ipsative tests compare relative strength of interests within an individual instead of comparing it to other professional groups, such as the interest inventories. Evidence-based testing is part of a worldwide trend to require proof that treatments and interventions yield measurable positive outcomes.