List of Psychological Test Instruments

Psychological assessments are used to measure intellectual and cognitive functioning, analyze personality traits, and assess symptoms of mental disorders and conditions. Tests may be oral or written and may include true/false, multiple choice and open-ended questions; people may be asked to describe pictures or rate feelings on a scale of one to ten. There are a great many psychological assessments; here are some of the most trusted and well known.

The most frequently used in-depth personality test is the Minnesota Multiphasic Personality Inventory (MMPI). It's a written (or electronically given) test including several hundred questions designed to measure mental wellness and psychopathology. The test measures 10 different types of psychopathology and includes questions intended to determine the test taker's honesty and overall attitude to the test itself.

Only a trained psychologist is allowed to administer, interpret or have access to the testing materials for the MMPI. It is the personality assessment most often relied on in court cases. There are less formal personality assessments online, such as the Kiersey Temperament Sorter, but they're generally not used in clinical or legal settings.

There are a number of tests used to measure intelligence quotient (IQ) using many different methods: visual puzzles, verbal questions, arithmetic or mathematical problems, tests of general knowledge and abstract reasoning questions among them. Two of the best-known are the Stanford-Binet Intelligence Scale, first developed at the beginning of the 20th century and revised five times since, and the Wechsler Intelligence Scales. Intelligence assessments are used in educational, workplace and treatment settings.

Psychologists have a variety of tests they use in determining diagnosis and treatment, many of which are essentially checklists of self-reported symptoms of conditions such as ADHD, anxiety, obsessive-compulsive disorder, bipolar disorder or schizophrenia. There are assessments designed to measure psychopathic thinking, or lack of empathy, that are designed to be hard to outwit. These assessments are used in disability evaluations, hospitals, prisons and therapeutic settings. There is an entire branch of study devoted to spotting fakers.

The more in-depth and complex a test, the more training is needed to correctly interpret its results. Since these test results can have serious impacts on an individual's future, poor design or improper administration or interpretation can be a serious problem. In the case of intelligence tests, factors such as pregnancy or illness can influence a person's cognitive ability temporarily, causing inaccurate results. There's also a growing awareness that there may be types of functional intelligence that are difficult or impossible to measure.