Personality Assessment

Projective Personality Tests

Projective personality assessments use unstructured tasks designed to reveal a person's unconscious desires. These tools lack reliability and validity but are still used in some clinical settings.

Psychoanalytic practitioners developed personality tests designed to reveal people's deepest feelings, impulses, and desires. These projective personality tests were designed to maximize ambiguity in the hopes that test takers would reveal unconscious aspects of their personality through their test responses. Projective tests show people ambiguous images or phrases and then ask people to tell a story, interpret an image, or complete a sentence.

One projective test is the Rorschach Inkblot Test, during which the psychologist asks the open-ended question, "What might this be?" when presenting a series of cards with ambiguous ink blots on them. This open-ended question invites the test-taker to access and reveal their unconscious thoughts and feelings. Other projective tests include the Thematic Apperception Test (TAT), which asks people to tell a story based on a black-and-white image of people, and the Rotter Incomplete Sentences Blank, which asks people to complete partial sentences. For example, people will write endings for partial sentences such as, "When I was a child ..." or "I need…." Their responses may help reveal their real feelings. Although these personality tests have been widely used for many years, they lack reliability and validity. They have not proven themselves useful in psychological diagnosis or predicting behavior. The ethical and legal shortcomings of these tests are especially important when making significant decisions, such as committing someone to a psychiatric hospital, making hiring decisions, or evaluating someone accused of a crime.

Projective Personality Assessment with Ambiguous Images

Projective personality assessments require test-takers to respond to ambiguous stimuli. On the Rorschach inkblot test, test-takers describe what they see in an image. Psychologists then evaluate aspects of these responses such as whether they are common, include the full image, and make sense given the shape of the image. Although once widely used, projective tests do a poor job of predicting behavior.

Objective Personality Tests

Psychologists have developed many reliable and valid questionnaires to assess personality traits. Normed tests can reveal how a person's personality traits compare to a selected group of people in general.

Most psychologists now assess personality using questionnaires that were developed and tested on large samples. These objective tests are not ambiguous like projective tests. Objective tests have clear response options (e.g., yes/no, true/false, numerical scales). The scales and subscales that make up objective tests can also be psychometrically tested to verify the reliability and validity of the constructs (a cluster of behaviors) being tested. One example of an objective test is the NEO Personality Inventory (NEO PI), a personality inventory that examines Big Five personality traits (openness to experience, conscientiousness, extraversion, agreeableness, and neuroticism) and subcategories of those traits. Scores on this measure are consistent over time and have been shown to predict behavior. The NEO-PI has been given to a large and representative sample of the population (individuals of different age ranges, ethnicities, and cultural backgrounds). The instrument has also been translated into many languages. Scores on the NEO-PI can reveal how an individual's personality traits compare to the general population.

The Sixteen Personality Factor (16PF) measures the traits identified by psychologist Raymond Cattell. On this scale, people rate the extent to which statements accurately describe them. It provides scores related to Big Five personality traits, as well as on subscales related to those traits. For example, the Neuroticism scale includes subscales that assess reactivity, vigilance, apprehensiveness, and tension.

Another commonly used test is the Minnesota Multiphasic Personality Inventory (MMPI). This test requires people to answer a series of true/false questions, leading to scores on 10 scales. Some scales provide information about personality traits, such as social introversion. Others provide information about clinical symptoms such as paranoia or depression. The MMPI also includes four validity scales. These scales help indicate whether a respondent is trying to make themselves look better or worse than they really are. They can also help catch a person who simply answered questions randomly. The MMPI is most often given in clinical settings to aid in diagnosis.

The Myers-Briggs Type Indicator (MBTI) was developed by Isabel Briggs Myers and Katharine Briggs. The test is intended to sort people according to Carl Jung's personality theories. The test produces scores that categorize people as introverted versus extraverted, sensing versus intuitive, thinking versus feeling, and judging versus perceptive. These classifications are combined to categorize people into one of 16 categories. For example, a person might be introverted, sensing, feeling, and perceptive (ISFP). This personality category comes with a description of a person's preferences and interpersonal style. This test is often used in the workplace to help coworkers understand each other's communication style and approach to decision making, or to help people choose careers. However, the evidence base for this test is poor. Research does not support these personality distinctions as the most crucial traits that distinguish individuals. The test also has issues with reliability. When people retake the test, they often fall in entirely different categories. Therefore, although the test is common in business settings, it is not used by clinical or research psychologists.