LO 13 Explain why reliability and validity are important in personality assessment.

Before we discuss the various types of personality tests, let’s get a handle on the qualities that render these tests effective—reliability and validity. Reliability can refer to two aspects of an assessment. Test–retest reliability is how consistent results are when the same person takes the test more than once. Suppose you take the same personality test today and tomorrow. From one day to the next, your personality is unlikely to change, so your results shouldn’t either. With a reliable test, the scores should be very similar at different points in time. Interrater reliability refers to the consistency across people scoring an assessment. With high interrater reliability, the results are the same regardless of who scores the test.

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The other important quality of a personality assessment is validity. A valid test is one that can be shown to measure what it intends to measure. Let’s say a psychologist develops an assessment for extraversion. In order for her test to be considered valid, it must yield results that are similar to already established and valid assessments of extraversion.

Assessment of personality can be broadly classified into objective and subjective measures. Findings from subjective assessments are based, in part, on personal intuition, opinions, or interpretations. With objective assessments, findings are based on a standardized procedure in which the scoring is free of opinions, personal beliefs, expectations, and values. Critics of subjective assessments suggest that there is not enough consistency across findings, as a result of nonstandard scoring procedures. And as noted in earlier chapters, humans are prone to a variety of biases and cognitive errors that can interfere with the ability to accurately assess people and situations. Critics of objective assessments contend that the standardization of these tests does not allow for flexibility and fails to appreciate the diversity of individual experiences. Despite these alleged flaws, many psychologists use a mixture of objective and subjective assessment techniques with their clients.

Not everyone agrees about the effectiveness of personality assessment. Even so, it is used in many contexts and in ways that have profound implications. Psychologists use personality tests to get to know their clients and diagnose mental disorders. Companies use them to make decisions about new hires and promotions (Does this person have what it takes to be a manager?). Personality tests are part of the battery of assessments used to evaluate the functioning of parents embroiled in custody disputes: Is mom depressed? Can she care for this child? (Lilienfeld, Wood, & Garb, 2005).

In this next section, we will explore the major types of personality tests that psychologists employ: interviews, projective personality tests, and objective personality tests. Many of these are aligned with specific perspectives (psychoanalytic or behavioral, for example), but most psychologists use an integrative approach, drawing on multiple perspectives in their assessment of clients.

One way to gather information about personality is through a face-to-face interview. In an unstructured, or open-ended, interview, there is no predetermined path. A psychologist might begin with a question like, “What brings you here today?” and then gently direct the conversation in a way that helps her understand her client’s strengths and weaknesses, hopes and plans. Semistructured and structured interviews, on the other hand, employ specific paths of questioning that hinge on the respondent’s answers. This format provides a more systematic means of comparing behaviors across individuals.

One great advantage of the interview is that it allows a psychologist to see a client in a relatively natural, realistic setting. Talking with a client face to face, a psychologist can observe facial expressions and body language, which may offer clues to what’s going on inside. There are drawbacks, however. Interview subjects may lie to the interviewer (without even realizing it), spin the facts to misrepresent themselves, or share memories that are distorted or incomplete. Another source of error is the interviewer. She may, for example, lead the interview in a particular direction or interpret responses in a way that reinforces her own beliefs about personality. Clients can also be influenced by the interviewers’ nonverbal language. The desire to answer “correctly” is strong in an interview format. Just as in surveys, the way a question is asked can have a profound influence on the answer.

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LO 14 Define projective tests and evaluate their strengths and limitations.

It’s a hot summer’s day and you’re lying on the beach, gazing at the clouds. “What do you see?” you ask your friend. “I see the profile of a Doberman pinscher,” she replies. “That’s funny,” you say. “I see a child doing jumping jacks.”

How is it possible that two people can look at the same image and come away with such different impressions? Some would argue that it has a lot to do with personality. The idea that personality influences perception is the premise of projective personality tests, which psychologists use to explore characteristics that might not be accessible through interview or observation, as they attempt to access aspects of the unconscious (Infographic 10.3). With this type of assessment, the test taker is shown a stimulus without a specified meaning and then prompted to project meaning onto it. Projective personality tests assume that people carry around anxiety and unresolved conflicts, often beneath conscious awareness. Because these tests attempt to uncover such issues indirectly, they are less threatening than other methods, and therefore provoke less resistance. The goal of the test administrator is to take the manifest content (what the person reports seeing) and try to understand its underlying meaning.

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THE RORSCHACH INKBLOTS The best-known projective personality test is the Rorschach. The original version of the test was developed by Swiss psychiatrist Hermann Rorschach (1884–1922) in 1921. Today’s psychologists typically use Rorschach inkblots with a comprehensive coding system introduced in the 1970s (Exner, 1980, 1986).

Here is a rough description of how the test is administered: Imagine someone hands you a series of cards covered in odd-looking blotches of ink—five cards with black-and-white blotches, and another five with color. Presenting the cards one by one, he asks you to report what you see. The images you describe and the details on which you focus will be important factors in the assessment of your personality, which involves a systematic comparison with answers given by other test takers who have known personality characteristics and diagnoses. Do you see bears playing patty cake? Seeing animals in motion might be interpreted as a sign of rashness. Are you homing in on the black areas? This could suggest a feeling of melancholy or sadness (Lilienfeld et al., 2005).

THE THEMATIC APPERCEPTION TEST (TAT) In the mid-1930s, Henry Murray and his colleagues developed the Thematic Apperception Test (TAT), a projective assessment that consists of 20 cards containing black-and-white illustrations of ambiguous scenes. When shown a card, the test taker is asked to tell a story about it. The story might incorporate a description of the people in the scene, and should include what led up to the scene, the emotions and thoughts of the characters, and a conclusion. The assumption is that the test taker will project underlying conflicts onto the ambiguous stimuli of the picture; the job of the test administrator is to unearth them.

TAKING STOCK One criticism of projective personality tests is that they can take too much time. However, because the test taker may be willing to speak openly, honestly, and freely due to the unstructured nature of the assessment, the benefits seem to outweigh the costs. Another major concern, mentioned earlier, is the subjectivity of interpreting results, which can lead to reliability problems. Test administrators may score differently, and test takers may not get the same results when they take the test on different occasions. Even the comprehensive scoring system for the Rorschach inkblots has not resolved concerns about projective tests, because the issue of validity remains. Many critics suggest projective tests are not valid because they do not measure what they claim to be measuring (Schultz & Schultz, 2013). Nonetheless, clinicians continue using projective tests because they often provide a way to begin forming a picture of a client.

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What tools do you use to get a feel for a person? Do you ever try to size up someone’s personality by looking at his Facebook page? In many cases, personality characteristics projected through social media bear close resemblance to real-world identities.

LO 15 Describe objective personality tests and evaluate their strengths and limitations.

Earlier we mentioned that clinicians use a variety of tools to assess the personalities of their clients. Among those tools are objective personality tests, assessments made up of a standard set of questions with answer choices (true/false, multiple choice, circle the number). These tests are called objective because the results are assessed in a standardized way, free of personal bias. In contrast to the projective inventories, which often seem to be overly subjective, objective personality tests have clear scoring instructions that are identical for anyone taking the test. Often scores are calculated by a computer. In addition to being convenient and unbiased, objective tests have a solid base of evidence supporting their reliability and validity (Anastasi & Urbina, 1997). Some of these tests may focus on a particular personality characteristic or trait (such as locus of control); others might assess a group of characteristics (such as the Big Five).

THE MMPI–2 The most commonly used objective personality test is the Minnesota Multiphasic Personality Inventory (MMPI–2; Butcher & Rouse, 1996). This self-report questionnaire includes more than 567 statements to which the individual responds “true,” “false,” or “cannot say.” Some of the items you might see on the MMPI–2 include statements such as “I often wake up rested and ready to go” or “I want to work as a teacher.” Since the original purpose of the MMPI was to identify disorders and abnormal behavior, it includes 10 clinical scales (such as, hypochondriasis and depression). It also has validity scales (such as the Lie scale and the Defensiveness scale) to assess the degree to which the results are useful. These validity measures help ensure that the person taking the assessment is not trying to appear either more disturbed or more healthy than she actually is. It is important to control for manipulation by the test taker because the MMPI is used in a variety of nonclinical settings—to inform decisions about custody or other legal matters, for example. Like other personality assessments, the MMPI has its share of criticisms. Since it was designed to help make diagnoses, many feel its application outside of therapeutic settings is inappropriate. The scales are based on groups of people exhibiting abnormalities, and therefore they may not translate to nonclinical populations.

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16PF Another objective assessment of personality is the Sixteen Personality Factor Questionnaire (16PF), originally created by Raymond Cattell and based on his trait theory. With the 16PF, the test taker must select one of three choices in response to 185 questions. Ultimately, a profile is constructed, which indicates where the person falls along the continuum of each of the 16 dimensions. Take a look at Figure 10.5 and you can see how pilots and writers compare on the 16 factors. For example, airline pilots tend to fall on the tough-minded end of the continuum, whereas writers tend to be located on the sensitive, tender-minded end (Cattell, 1973a).

MYERS–BRIGGS One very popular objective assessment of personality is the Myers–Briggs Type Indicator (MBTI) (Briggs & Myers, 1998). Katherine Briggs and her daughter Isabel Briggs-Myers created this assessment in the 1940s. It designates a personality “type” as it relates to the following four dimensions: extraversion (E) versus introversion (I); sensing (S) versus intuiting (N); thinking (T) versus feeling (F); and judgment (J) versus perception (P). For example, someone characterized as ISTP would be introverted, rely on the senses (rather than intuition) to understand the environment, favor logic over emotion, and focus on using perception as opposed to judgment.

Problems arise when assessments incorporate somewhat vague descriptions of personality traits. Some would even liken it to the Barnum effect, which was named after P. T. Barnum (1810–1891), who was famous for his ability to convince people he could read minds. Essentially, he did this by making generally complimentary and vague statements that could be true about anyone (You are creative and work well with others and you sometimes procrastinate, but ultimately you get the job done). Similarly, with the MBTI, the personality type descriptions are “generally flattering and sufficiently vague so that most people will accept the statements as true of themselves” (Pittenger, 1993, November, p. 6). Although the MBTI is quite popular, the research supporting it is weak, especially as it relates to job performance, career choices, and related matters (Pittenger, 2005). Because the test results don’t always correlate with job success, the validity of the assessment is questionable. In addition, the test–retest reliability is not always strong. A person can take the test twice and end up with different results (Hunsley, Lee, & Wood, 2003; Pittenger, 2005).

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TAKING STOCK We have noted specific criticisms of the MMPI-2 and Myers–Briggs tests, but there are other serious drawbacks of objective assessments. Although many of these tests include some sort of mechanism for checking the validity of the test taker’s answers, people may lie (and get away with it), particularly when the assessment results may impact some important aspect of their lives, such as work or a child custody case. In addition, social desirability can influence the results; individuals may unintentionally answer questions in a way that makes them “look better” to others.

Can we be 100% confident in the results of personality tests? Not yet, but psychologists are developing new measures that take advantage of technology, bypassing self-report as much as possible. For example, scanning technology has been used to identify particular areas of the brain associated with personality expression. One group of researchers made use of fMRI in their effort to tease apart the relationship between personality and mood states. They found that activity in the anterior cingulate sometimes was associated with extraversion, possibly identifying an area of the brain involved in extraversion and introversion (Canli, Amin, Haas, Omura, & Constable, 2004). Perhaps future technologies will enable more precise assessment of personality characteristics (Eisenberger, Lieberman, & Satpute, 2005).

Question 1

1. Objective

2. Projective

3. 16PF

4. Myers–Briggs

Question 2

1. intuition or bias.

2. reliability.

3. validity.

4. objectivity.

Question 3