Mental health treatment was seen as a medical treatment before the second world war, explaining why psychologists were not allowed to treat patients without supervision. After the second world war, there was an increased need for psychological help (e.g. shellshock patients) which led to a more psychological approach to mental disorders.

After the second world war, there was the rise of antipsychiatry (1), treatments requiring scientific evidence (2) and medication being used for mental disorders (3).

People tend to believe that mental disorders are rooted in the brain as a result of psychiatry’s origin in medicine. This view was strengthened by the discovery that certain drugs can alleviate the symptoms of mental disorders.

Charcot and Freud started to see psychiatric symptoms as expressions of diseases, positing psychological factors as the causes of symptomatology. Neurosis refers to unconscious conflicts which express themselves in symptomology.

Rogers introduced humanistic psychology based on the acceptance of patients. In humanistic psychology, a good therapist has unconditional positive regard (1), empathetic understanding (2) and congruence. Congruence refers to the therapist being genuine in his support and understanding. Cognitive behavioural therapy is based on a psychological approach to mental disorders.

The medical and psychological view of mental disorders naturalizes mental disorders as they both view mental disorders as a part of nature which can be systematically studied and understood. This got rid of supernatural explanations for mental disorders.

Extreme naturalization refers to the idea that mental disorders deviate from the norm and that the norm itself might be flawed rather than the patients. Antipsychiatry states that mental disorders do not exist and only norms for normal exist. However, increasing prevalence of mental disorders might indicate a change in society rather than a change in people.

The psychological test is an instrument that probes a person and the person’s response is used to infer a psychological state or attribute. It needs to take reliability (1), validity (2), bias (3) and random measurement error (4) into account. A test contains the condition of intent (1), is administered as an indication of some condition (2) and involves a difference in status between the test-giver and test-taker (3).

There are three types of psychological test:

1. Authenticity test
   This is a test to determine whether a person is genuine and to determine whether a person is guilty or innocent.
2. Qualifying test
   This is a test to determine the fittest person for a particular task.
3. Diagnostic test
   This is a test to determine which condition a person suffers from.

An achievement test (i.e. the form of the qualifying test) is a standardised test which measures the knowledge of a particular topic or set of topics. Tests were created to prevent bias and unfairness as tests are more reliable and less biased than teacher judgements.

Meritocracy refers to a society based on ability. Educational tests serve meritocracy as psychological tests (e.g. educational tests) can be used to legitimize exercising power. Psychological tests aid the discrimination of people based on ability. There is a societal price to meritocracy, although cognitive ability is associated with better outcomes.

There is a strong evaluative component of IQ tests as deciding that one ethnic group has a lower IQ than another ethnic group is seen as a societal threat because of eugenics (1) and institutionalized racism (2).

Psychology has changed society deeply by inventing the psychological test and psychometrics to evaluate the properties of the psychological test. In society, there is increased use of psychological tests because it is the best way to make assessments about people (1), society uses more science-based evidence to make decisions (2) and because there is a growing individualisation in society and psychological tests allows for distinguishing people (3).

There are five reasons why flawed, classic studies keep being cited and used:

1. The story is too good not to be true.
2. The original research is biased and later generations did not check the evidence.
3. The underlying message is correct.
4. The story is good for psychologists.
5. The story is good for management.