Doctors, researchers, and employers use personality assessments for a variety of reasons:
- Clinical psychologists often use assessments as aids for diagnosing psychological disorders.
Example: A psychologist might administer personality tests to a patient with a varied set of symptoms to narrow down possible diagnoses. In such a case, a psychologist would typically use a battery of tests in addition to interviewing the patient.
- Some mental health providers use tests to decide how best to counsel people about normal problems of daily living.
Example: A counselor might administer a personality test in order to help a person choose a career.
- Some organizations use assessments to select personnel to hire, although this practice is decreasing in popularity.
Example: A consulting firm might assess job candidates in order to decide which candidates would be likely to perform well under pressure.
- Researchers frequently use tests in the course of studying personality traits.
Example: A researcher studying the correlation between risk taking and criminality might administer a personality test to a sample of prison inmates.
Three important ways of assessing personality include objective tests, projective tests, and assessment centers.
Objective Personality Tests
Objective personality tests are usually self-report inventories. Self-report inventories are paper-and-pen tests that require people to answer questions about their typical behavior. Commonly used objective tests include the MMPI-2, the 16PF, and the NEO Personality Inventory.
The Minnesota Multiphasic Personality Inventory (MMPI) was developed in the 1940s and revised in the 1980s. The revised version is called the MMPI-2. The MMPI-2 contains a list of 567 questions. People taking the test must answer these questions with true, false, or cannot say.
The MMPI was originally developed to help clinical psychologists diagnose psychological disorders. To interpret the MMPI-2, psychologists divide the answers to questions into fourteen subscales. Ten of these subscales are clinical subscales, which give information about different aspects of the test taker’s personality. The other four subscales are validity subscales, which indicate whether the test taker was careless or deceptive when answering questions. A score on any single subscale doesn’t provide a clear indication of a specific psychological disorder. Rather, the score profile, or pattern of responses across subscales, indicates specific psychological disorders.
The Sixteen Personality Factor Questionnaire (16PF) is a test that assesses sixteen basic dimensions of personality. It consists of a list of 187 questions.
The NEO Personality Inventory
The NEO Personality Inventory measures the Big Five traits: extraversion, openness to experience, agreeableness, conscientiousness, and neuroticism.
Advantages and Disadvantages of Self-Report Inventories
Self-report inventories are useful because they allow psychologists to get precise answers to standardized questions. In other words, all subjects who take a test answer the same questions, and all subjects have to select answers from the same range of options. Inventories are also objective, which means that different people scoring the same test would score them in the same way. However, these scores might be interpreted differently by different people.
There are several disadvantages to self-report inventories as well:
- Self-report inventories often contain transparent questions, which means subjects can figure out what a psychologist wants to measure. Therefore, subjects can lie intentionally and fake personality traits they don’t really have. Researchers who develop tests address this problem by including lie scales in tests, which provide information about the likelihood that a subject is lying.
- The social desirability bias can affect responses on self-report inventories. In other words, when filling out an inventory, people might state what they wish were true, rather than what is true. Test developers can minimize this bias by dropping questions that are likely to evoke it.
- People sometimes don’t understand the questions on the test. Test developers try to address this issue by wording questions very clearly so that they have only one possible interpretation.
- People sometimes don’t remember aspects of the experience they are asked about.
Projective Personality Tests
Projective personality tests require subjects to respond to ambiguous stimuli, such as pictures and phrases, that can be interpreted in many different ways. Projective tests are based on the projective hypothesis, which is the idea that people interpret ambiguous stimuli in ways that reveal their concerns, needs, conflicts, desires, and feelings.
Clinical psychologists and researchers often use two projective tests: the Rorschach test and the Thematic Apperception Test.
The Rorschach Test
The Rorschach test consists of a series of ten inkblots. Psychologists ask subjects to look at the inkblots and describe what they see, and the psychologists then use complex scoring systems to interpret the subjects’ responses. Scores are based on various characteristics of responses, such as the originality of the response and the area of the blot described in the response. The Rorschach gives psychologists information about the subject’s personality traits and the situational stresses the subject may be experiencing.
The Thematic Apperception Test
The Thematic Apperception Test (TAT) consists of a series of pictures containing a variety of characters and scenes. Psychologists ask subjects to make up stories about each picture and look for themes that run through the subjects’ responses. For example, a person with a high need for achievement may consistently come up with stories that have achievement-related themes.
Advantages and Disadvantages of Projective Tests
Projective tests are useful because they allow psychologists to assess unconscious aspects of personality. Projective tests are also not transparent: subjects cannot figure out how their responses will be interpreted. Therefore, subjects cannot easily fake personality traits on a projective test.
A serious disadvantage of projective tests is that they have questionable reliability and validity. Despite this flaw, many researchers and clinicians find that such tests give them useful information.
Assessment centers allow psychologists to assess personality in specific situations. In assessment centers, subjects are made to face situations in which they must use particular types of traits and skills, and their performance is then assessed. Assessment centers work on the well-accepted idea that the best predictor of future behavior is past behavior in similar situations. For example, a corporation may select a person for a managerial position by placing candidates in a simulated managerial situation for half a day and assessing their performance.
Assessment centers are useful for selecting personnel for positions of responsibility because they predict how people will act in challenging situations. However, assessment centers are expensive and time consuming.