Psychological assessment may come in two forms: formal and informal. Formal assessment involves the use of tools such as tests, questionnaires, checklists and rating scales, while in informal assessment the interview/evaluation usually lacks such structure or organization. In either case, the psychologist will typically start by asking questions.
Formal assessment, often referred to as psychological evaluation, is generally performed by a licensed psychologist when a problem, that does not have a physical origin, is noticed and the cause needs to be determined. This problem can exist in several realms, for example: (1) inappropriate behavior (2) inappropriate mood states (3) failure to perform up to expected standards (as in schoolwork).
The purpose of evaluation is to determine what is happening in the individual's psychological life that may be blocking their ability to behave (or feel) in a more appropriate and constructive manner. Testing cannot necessarily pinpoint the precise cause of the disturbance, especially if it is a complex emotional issue, but it will give a number of clues that can help the individual, parent and/or professional go in the right direction. In some cases that are more specific, such as dyslexia or other learning disability, testing will let the parent and teacher know exactly what steps need to be taken to help the child/adolescent learn.
Generally, a full battery of psychological tests can take several hours to administer (often administered to a child in several one to two hour time periods to avoid fatigue). It takes several more hours for the professional to score and interpret the test results and to write a report suitable for school personnel or a psychotherapist to use in developing a curriculum or treatment plan. Occasionally, a psychologist will determine that only a few tests from the full battery need to be administered to pinpoint or rule out a particular problem and thus avoid an unnecessarily lengthy and expensive procedure. Whichever you and the professional determine is necessary, the results should yield a wealth of information useful to the individual, parents, educational institution or other professionals to make one’s emotional, educational and/or vocational life more healthy, satisfying and successful.