Psychological testing — also called psychological assessment — is the foundation of how psychologists better understand a person and their behavior. It is a process of problem solving for many professionals — to try and determine the core components of a person’s psychological or mental health problems, personality, IQ, or some other component. It is also a process that helps identifies not just weaknesses of a person, but also their strengths.
Psychological testing measures an individual’s performance at a specific point in time — right now. Psychologists talk about a person’s “present functioning” in terms of their test data. Therefore psychological tests can’t predict future or innate potential.
Psychological testing is not a single test or even a single type of test. It encompasses a whole body of dozens of research-backed tests and procedures of assessing specific aspects of a person’s psychological makeup. Some tests are used to determine IQ, others are used for personality, and still others for something else. Since so many different tests are available, it’s important to note that not all of them share the same research evidence for their use — some tests have a strong evidence base while others do not.
Psychological assessment is something that’s typically done in a formal manner only by a licensed psychologist (the actual testing may sometimes be administered by a psychology intern or trainee studying to become a psychologist). Depending upon what kind of testing is being done, it can last anywhere from 1 1/2 hours to a full day. Testing is usually done in a psychologist’s office and consists largely of paper-and-pencil tests (nowadays often administered on a computer for ease-of-use).
Psychological testing is divided into four primary types:
- Clinical Interview
- Assessment of Intellectual Functioning (IQ)
- Personality Assessment
- Behavioral Assessment
In addition to these primary types of psychological assessment, other kinds of psychological tests are available for specific areas, such as aptitude or achievement in school, career or work counseling, management skills, and career planning.
The Clinical Interview
The clinical interview is a core component of any psychological testing. Some people know the clinical interview as an “intake interview”, “admission interview” or “diagnostic interview” (although technically these are often very different things). Clinical interviews typically last from 1 to 2 hours in length, and occur most often in a clinician’s office. Many types of mental health professionals can conduct a clinical interview — psychologists, psychiatrists, clinical social workers, psychiatric nurses, amongst others.
The clinical interview is an opportunity for the professional to gather important background and family data about the person. Think of it as an information-gathering session for the professional’s benefit (but ultimately for your benefit). You may have to recall or review a lot of your life and personal history with the professional, who will often ask specific questions about various stages in your life.
Some components of the clinical interview have now become computerized, meaning you will answer a series of questions on a computer in the clinician’s office instead of talking directly to a person. This is most often done for basic demographic information, but can also include structured diagnostic interview questions to help the clinicians formulate an initial diagnostic impression.
Before any formal psychological testing is done, a clinical interview is nearly always conducted (even if the person has already gone through one with a different professional). Psychologists conducting the testing will often want to form their own clinical impressions, which can be best done through a direct interview with the person.
Assessment of Intellectual Functioning (IQ)
Your IQ — intellectual quotient — is a theoretical construct of a measure of general intelligence. It’s important to note that IQ tests do not measure actual intelligence — they measure what we believe might be important components of intelligence.
There are two primary measures used to test a person’s intellectual functions — intelligence tests and neuropsychological assessment. Intelligence tests are the more common type administered and include the Stanford-Binet and the Wechsler scales. Neuropsychological assessment — which can take up to 2 days to administer — is a far more extensive form of assessment. It is focused not just on testing for intelligence, but also on determining all of the cognitive strengths and deficits of the person. Neuropsychological assessment is most usually done with people who have suffered some sort of brain damage, dysfunction or some kind of organic brain problem, just as having a brain hemorrhage.
The most commonly administered IQ test is called the Wechsler Adult Intelligence Scale—Fourth Edition (WAIS-IV). It generally takes anywhere from an hour to an hour and a half to administer, and is appropriate for any individual aged 16 or older to take. (Children can be administered an IQ test especially designed for them called the Wechsler Intelligence Scale for Children – Fourth Edition, or the WISC-IV.)
The WAIS-IV is divided into four major scales to arrive at what’s called a “full scale IQ.” Each scale is further divided into a number of mandatory and optional (also called supplemental) subtests. The mandatory subtests are necessary to arrive at a person’s full scale IQ. The supplemental subtests provide additional, valuable information about a person’s cognitive abilities.
Verbal Comprehension Scale
- Supplemental Subtest: Comprehension
Perceptual Reasoning Scale
- Block Design
- Matrix Reasoning
- Visual Puzzles
- Supplemental Subtests: Picture Completion; Figure Weights (16-69) only
Working Memory Scale
- Digit Span
- Supplemental Subtest: Letter-Number Sequencing (16-69 only)
Processing Speed Scale
- Symbol Search
- Supplemental Subtest: Cancellation (16-69 only)
As you can surmise from the names of some of the scales of the test, measuring IQ isn’t just answering questions about information or vocabulary. Because some of the subtests require physical manipulation of objects, the Wechsler is tapping into many different components of a person’s brain and thought processes (including the creative). For this reason and others, online IQ tests are not equivalent to real IQ tests given by a psychologist.