Psychological Testing: What It Is and Why It Is Used
What it Is
Psychological testing, or psychological assessment, is the use of measures designed by mental health professionals to determine certain characteristics about the individual being tested.
The basic idea is to get samples of an individual's behavior in particular situations and use that to make assumptions/estimations about his or her behavior in the world at-large.
There are three major domains of assessment:
- Intellectual Assessment
- Psychodiagnostic Assessment
- Neuropsychological Assessment
This type of assessment is most often used to determine the most appropriate educational setting for a child. Specifically, it is primarily used to decide whether or not a child should be placed in an advanced program, has global developmental delay, or has a learning disorder.
Intellectual assessment often consists of two types of tests: (1) an intelligence test, and (2) an achievement test.
Most succinctly, an intelligence test is used to measure a child's aptitude -- that is, how much they are capable of learning. These tests give an IQ (intelligence quotient) score, where 100 represents an average IQ. Most individuals - regardless of age - will score between 85 and 115, which are within the "average" range.
An achievement test is used to assess how much an individual has learned up to this point, focusing more on what one might expect someone to have learned in school up to their age. These test are also often scored with an average of 100, and with most scores falling between 85 and 115.
If a child has an IQ score of above 115, he or she may likely be considered for an advanced placement, or "gifted," program, regardless of achievement test score. [Learn more about giftedness here.]
If a child has an IQ score of below 85, he or she may be considered for a special learning class and may be further assessed for developmental delays (previously known as mental retardation). [Learn more about developmental delay here.]
Regardless of IQ score, if a child's achievement score is 22+ points below his/her IQ score, he/she will likely be diagnosed with a learning disorder. [Learn more about learning disorders here.]
Intellectual assessment may also include additional test to further understand an examinee's level of development and needs.
When used with adults, it may be intended to determine how much support he/she needs -- this is usually done when developmental delay is suspected.
Intellectual tests may also be used for certain jobs, and the United States Military uses a particular type of intelligence/achievement test to assess the skills and functioning levels of prospective enlisted personnel.
Psychodiagnostic assessment may most often be used to provide insight into diagnosing a client, to gain a broader sense of the ways in which he or she interpret and interacts in the world, and for self-help purposes.
These tests include:
- the ever-famous Rorschach projective test,
- various personality measures (e.g. Millon Clinical Multiaxial Inventory and Minnesota Multi-Phasic tests),
- story-telling measures (e.g. Thematic Apperception Test),
- self-report subjective experience tests (e.g. Beck Depression Inventory)
- and miscellaneous other tests of functioning level (e.g. Child Behavioral Checklist)
While these represent too large of a group of tests to delve into much here, all these measures provide different kinds of information and are used for different purposes.
Projective tests, like the Rorschach indicated above, are intended to give examiners a sense of how an individual makes decisions and organizes the world. This kind of information is most useful when determining a diagnosis, making court recommendations, and making more broad statements about the ability of an individual to function in the world.
Personality measures can range from simple tests designed for career development/selection to measures with in excess of 700 questions that assess for severe personality disturbances. In this particular category, the choice of the right measure is particularly important.
Story-telling measures are also considered projective tests and again deal with how an individual interprets events and organizes them. They are also often used with children to assess for abuse, since much information can be gleaned from the types of stories children tell.
Self-reports of subjective experiences are most often used to aid in diagnosis and/or to track the progress of a client throughout treatment. This most often includes measures of mood/affect during the recent past, not long-term information.
Finally, other measures can assess different perspectives on a situation, more concrete information, and miscellaneous information of interest to a clinician.
Neuropsychological assessment is a very specialized field and generally has one main purpose: to assess any brain deficits that are or may be present.
These tests are most often used in hospital settings to determine if and what kind of brain damage an individual may have. They are also used to assess for amnesia and other types of memory loss.
Measures can include having the examinee manipulate objects, view objects and report on them, and many other types of interaction.
Because the field is so specialized and the types of tests used varies so much depending on the suspected deficit, little more can be said without engaging in a year-long graduate course.