The typical approach would involve personality questionnaires or interviews. Basically, psychological instruments are used to gauge a person’s typical thoughts, feelings and behaviours.

Personality traits do confer risk and protection regarding mental health. For example, people who score high on measures of emotional stability are at reduced risk for developing diagnosable episodes of mental illness.

Personality can change in some cases, but in many cases, it may be helpful to think about healthier ways of expressing more risky personality tendencies. For example, a person who craves excitement might meet those needs through less dangerous activities (for example, exciting sports) than involvement with illicit substances.

Anger can have many causes, but people who describe themselves as angry all the time with little provocation may find it helpful to seek professional services aimed at understanding the sources of persistent angry feelings.

Personality traits can and do change for specific people. In many cases, it may also be helpful to think about ways of managing specific traits. For example, if someone is highly neurotic, they are sensitive to possible signs of threat in the environment. This sort of person can learn to better gauge the reality of those threat signals, focusing on how to manage the negative emotions that accompany neuroticism through building skills aimed at determining how concerning various threats might be in actuality.

Personality trait assessment is agnostic about the aetiology (underlying cause) of personality variation. Genetic factors are relevant to our personality tendencies, but they are not deterministic, and the environment plays a major role in shaping personality throughout the life course.