Psychologists are highly trained professionals with expertise in the areas of human behavior, mental health assessment, diagnosis and treatment, and behavior change. Psychologists develop and apply procedures based on psychological principles, to help people understand and change their thoughts, emotions and behaviors. Psychologists undergo several years of graduate education, training and research activities before receiving a postgraduate degree. Psychologists in applied practice must also complete at least one year of post-degree supervised employment in psychology before being licensed to practice independently. Licensed psychologists typically provide psychotherapy, counseling, and assessment/diagnostic services, which may include psychological testing. A skill unique to psychologists among all mental health professionals, psychological testing includes the measurement of personality, mental abilities, mental health concerns, aptitudes and interests, and other areas of psychological functioning. Psychologists must be licensed by the state or jurisdiction in which they practice. Licensure laws are intended to protect the public by limiting licensure to those persons qualified to practice psychology as defined by state law.

Psychological tests were created for three main reasons, all of which are interconnected:

It’s easier to get information from tests than by clinical interview. Most people won’t talk about this, but, believe it or not, many psychologists are rather inept at dealing with people, and so it’s a great relief to them to be able to administer a test rather than conduct a competent interview. Thankfully, such psychologists tend to specialize in testing (or research, or teaching) rather than psychotherapy. Think about this if ever you find yourself sitting in front of a steely-eyed psychologist while being given a battery of psychological tests.

The information from tests is more scientifically consistent than the information from a clinical interview. If a psychologist is simply trying to arrive at a diagnosis to help determine the course of psychotherapy, an interview is just fine. But when decisions have to be made about legal matters, disability issues, and so on, then the standardized information from tests allows one person to be directly compared with others, and it makes things more fair.

It’s harder to get away with lying on a test than in a clinical interview. Many tests have multiple “alarms” that go off when a test taker tries to lie. And some tests, such as the Rorschach (the “inkblot test”) don’t even give a clue as to what preferred, or healthy, responses might be, so it’s pretty much impossible to make yourself “look good” by fabricating deceptive answers to a test like this.