Objective Personality Tests
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/objectiv.htm, accessed 08 Oct 2008
The best known objective personality test is the MMPI. This test was created primarily to measure psychopathology. It contains several validity scales to determine if the client is responding to the questions accurately and truthfully, and it also contains ten basic clinical scales. Hundreds of additional scales have been created for the MMPI to measure virtually every personality trait and emotion conceivable. The MMPI was recently revised; the MMPI-2 is now the more commonly used edition. The MMPI is interpreted by looking at scale elevations and configurations. Although limited interpretation can be done by computer programs, a skilled psychologist is needed to make accurate interpretation which take into account a person's background and other test data. The MCMI-III is another test similar to the MMPI. It contains scales which closely correspond to the diagnoses in DSM-IV. It is particularly useful for the diagnosis of personality disorders. Other objective tests, such as the 16PF and the Myers-Briggs are more useful for looking at personality in the normal range, and are more helpful for counseling as opposed to psychiatric treatment.
Brief Summary of MMPI Scales:
Please note that the following is a very simplistic summary. If you have your own or someone else's MMPI results you should not draw conclusions based on what you see below. If you are not familiar with this test, you should rely on the judgment of a psychologist who is specifically trained and experienced with both the MMPI and testing in general. A professional can take into account demographic and other factors and understands the psychometric strengths and weakness of this test. S/he can also interpret score configurations, rather than taking a single score out of context.
With all that in mind, a high score on these scales indicates:
L: Reluctance to admit minor and common moral weaknesses
F: Tendency to exaggerate problems
K: Reluctance to reveal problems
1: Overconcern regarding physical problems
2: Depression
3: Tendency to repress and deny problems; shallow relationships
4: Rebelliousness; disregard for social conventions; authority conflict
5: Males: Sensitivity and cultural interests/Females: Assertiveness
6: Distrust
7: Chronic anxiety and obsessive-compulsive tendencies
8: Feelings of being overwhelmed; loss of contact with reality
9: High energy level which is not directed; grandiosity.
0: Shyness
Myers-Briggs
The Myers-Briggs, perhaps more than any other objective personality test, has captured popular imagination. This doesn't necessarily reflect better validity or accuracy than other tests, but more likely represents the ease of interpretation and broad application.
The Myers-Briggs consists of four scales, each of which places the test-taker as one of two personality classifications, based on Carl Jung's theories. Combining these scales results in 2 X 2 X 2 X 2 = 16 personality types.
The four scales are:
Attitudes: Extraversion (E) / Introversion (I): E types tend to become energized by action and interaction with others; I types tend to prefer reflection and calm, and become drained by action.
Functions (S/N): Sensing (S) / iNtuition (N): S types trust tangible information. N types trust abstract, theoretical information and are more likely to believe in "hunches."
Functions (T/F): Thinking (T) / Feeling (F): F types prefer to reach consensus on decisions and strongly empathize with others. T types tend to remain more objective, using reason and logic to reach decisions.
Lifestyles: Judging (J) / Perception (P): Judging types prefer to have matters settled. P types would rather keep options open.
The Myers-Briggs has wide application, including vocational and relationship counseling. A description of each of the 16 personality types can be found at the Myers-Briggs Foundation website.
Wednesday, October 8, 2008
testing for LDs
Re: Testing for Learning Disabilities
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/learning.htm, accessed 08 Oct 2008
Psychological testing is crucial for the diagnosis of learning disability. A learning disability is diagnosed when a specific ability, such as reading, is significantly lower than a person's general ability, usually measured by an IQ test. Specific abilities can be measured with academic achievement tests such as the Woodcock-Johnson.
The DSM-IV (psychiatric diagnostic manual) lists these learning disorders:
Reading Disorder: Reading skills are weaker than general ability. Can included ability to decode words and/or reading comprehension. Another term for reading or writing disorders is Dyslexia.
Disorder of Written Expression: Writing skills are weaker than general ability. Can include the quality of written expression, spelling, and/or writing syntax.
Mathematics Disorder: Calculation skills are weaker than general ability.
Learning Disorder, Not Otherwise Specified: Can be diagnosed when there is a mild deficit in two or three of the areas listed above (reading, writing, and math) that individually fall short of diagnostic criteria, but together can be considered as a significant impairment.
Other Learning Disorders: Other disorders are often diagnosed in educational settings, but are not listed in the DSM-IV. These include Auditory Processing Disorder (verbal skills weaker than nonverbal) or Visual Processing Disorder (spatial skills weaker than verbal).
Testing can also be used to diagnose or rule out attention deficit disorders. A continuous performance test, performance on certain IQ subtests, and teacher and/or parent reports can be combined to make a definitive and accurate diagnosis.
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/learning.htm, accessed 08 Oct 2008
Psychological testing is crucial for the diagnosis of learning disability. A learning disability is diagnosed when a specific ability, such as reading, is significantly lower than a person's general ability, usually measured by an IQ test. Specific abilities can be measured with academic achievement tests such as the Woodcock-Johnson.
The DSM-IV (psychiatric diagnostic manual) lists these learning disorders:
Reading Disorder: Reading skills are weaker than general ability. Can included ability to decode words and/or reading comprehension. Another term for reading or writing disorders is Dyslexia.
Disorder of Written Expression: Writing skills are weaker than general ability. Can include the quality of written expression, spelling, and/or writing syntax.
Mathematics Disorder: Calculation skills are weaker than general ability.
Learning Disorder, Not Otherwise Specified: Can be diagnosed when there is a mild deficit in two or three of the areas listed above (reading, writing, and math) that individually fall short of diagnostic criteria, but together can be considered as a significant impairment.
Other Learning Disorders: Other disorders are often diagnosed in educational settings, but are not listed in the DSM-IV. These include Auditory Processing Disorder (verbal skills weaker than nonverbal) or Visual Processing Disorder (spatial skills weaker than verbal).
Testing can also be used to diagnose or rule out attention deficit disorders. A continuous performance test, performance on certain IQ subtests, and teacher and/or parent reports can be combined to make a definitive and accurate diagnosis.
projective tests: intro
Re: Projective Tests
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/blots.htm, accessed 08 Oct 2008
The best known projective psychological test is the Rorschach, or inkblot test. The patient is asked to look at each blot and to say what it looks like or what it could be. Because the stimulus is ambiguous, the patient must impose his or her own structure. In doing so, thoughts, feelings, and themes, some of which are unconscious, are projected into the material. Projective tests tend to have lower validity and reliability than objective tests. That is, they are less stable, and have lower relationships with other criteria. However, the information which they provide tends to be richer and more varied.
The Rorschach test is particularly useful for detecting the types of disordered thought patterns seen in schizophrenia and other psychotic disorders. The scoring of this test takes into account the popularity of the patient's responses, the content of the responses, whether the figures are seen as moving or stationary, response complexity, whether color or shading is used, and other factors. As with most tests, there are no single responses which are seen as necessarily pathological. Response frequencies and ratios are compared to normal and abnormal averages to determine if pathology or a particular tendency is present.
Other projective tests include the Thematic Apperception Test (TAT), in which the patient tells stories about pictures, the Sentence Completion test, Draw-A-Person, and House-Tree-Person. The TAT is often used in a test battery in conjunction with the Rorschach. The TAT provides information about important themes in a person's life or the content of their thinking, whereas the Rorschach provides information about the process and form of a person's thoughts.
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/blots.htm, accessed 08 Oct 2008
The best known projective psychological test is the Rorschach, or inkblot test. The patient is asked to look at each blot and to say what it looks like or what it could be. Because the stimulus is ambiguous, the patient must impose his or her own structure. In doing so, thoughts, feelings, and themes, some of which are unconscious, are projected into the material. Projective tests tend to have lower validity and reliability than objective tests. That is, they are less stable, and have lower relationships with other criteria. However, the information which they provide tends to be richer and more varied.
The Rorschach test is particularly useful for detecting the types of disordered thought patterns seen in schizophrenia and other psychotic disorders. The scoring of this test takes into account the popularity of the patient's responses, the content of the responses, whether the figures are seen as moving or stationary, response complexity, whether color or shading is used, and other factors. As with most tests, there are no single responses which are seen as necessarily pathological. Response frequencies and ratios are compared to normal and abnormal averages to determine if pathology or a particular tendency is present.
Other projective tests include the Thematic Apperception Test (TAT), in which the patient tells stories about pictures, the Sentence Completion test, Draw-A-Person, and House-Tree-Person. The TAT is often used in a test battery in conjunction with the Rorschach. The TAT provides information about important themes in a person's life or the content of their thinking, whereas the Rorschach provides information about the process and form of a person's thoughts.
neuropsych testing: intro
Re: Neuropsychological TestingFr: Jon Rich, PhD, http://www.psychologicaltesting.com/neuropsy.htm, accessed 08 Oct 2008
The Luria-Nebraska and Halstead-Reitan test batteries are the best known and most commonly used neuropsychological measures. By using such measures, neuropsychologists can detect and localize organic brain impairment, and develop rehabilitation programs for cognitively impaired individuals. A neuropsychologic evaluation is more sensitive to the functional manifestations of brain impairment than neurological tests, such as an MRI or CAT scan.
The Luria-Nebraska and Halstead-Reitan test batteries are the best known and most commonly used neuropsychological measures. By using such measures, neuropsychologists can detect and localize organic brain impairment, and develop rehabilitation programs for cognitively impaired individuals. A neuropsychologic evaluation is more sensitive to the functional manifestations of brain impairment than neurological tests, such as an MRI or CAT scan.
chars of a good test
Re: What makes a good test?
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/val.htm, accessed 08 Oct 2008 (caps beyond main headings mine)
There are three basic elements to look for when judging the quality of a psychological test -- reliability, validity, and standardization.
RELIABILITY is a measure of the test's consistency. A useful test is consistent over time. As an analogy, think of a bathroom scale. If it gives you one weight the first time you step on it, and a different weight when you step on it a moment later, it is not reliable. Similarly, if an IQ test yields a score of 95 for an individual today and 130 next week, it is not reliable. Reliability also can be a measure of a test's internal consistency. All of the items (questions) on a test should be measuring the same thing -- from a statistical standpoint, the items should correlate with each other. Good tests have reliability coefficients which range from a low of .65 to above .90 (the theoretical maximum is 1.00).
VALIDITY is a measure of a test's usefulness. Scores on the test should be related to some other behavior, reflective of personality, ability, or interest. For instance, a person who scores high on an IQ test would be expected to do well in school or on jobs requiring intelligence. A person who scores high on a scale of depression should be diagnosed as depressed by mental health professionals who assess him. A VALIDITY COEFFICIENT reflects the degree to which such relationships exist. Most tests have validity coefficients (correlations) of up to .30 with "real world" behavior. This is not a high correlation, and emphasizes the need to use tests in conjunction with other information. Relatively low correlations mean that some people may score high on a scale of schizophrenia without being schizophrenic and some people may score high on an IQ test and yet not do well in school. Correlations [as] high as .50 are seen between IQ and academic performance.
STANDARDIZATION is the process of trying out the test on a group of people to see the scores which are typically obtained. In this way, any test taker can make sense of his or her score by comparing it to typical scores. This standardization provides a mean (average) and standard deviation (spread) relative to a certain group. When an individual takes the test, she can determine how far above or below the average her score is, relative to the normative group. When evaluating a test, it is very important to determine how the normative group was selected. For instance, if everyone in the normative group took the test by logging into a website, you are probably being compared to a group which is very different from the general population.
Fr: Jon Rich, PhD, http://www.psychologicaltesting.com/val.htm, accessed 08 Oct 2008 (caps beyond main headings mine)
There are three basic elements to look for when judging the quality of a psychological test -- reliability, validity, and standardization.
RELIABILITY is a measure of the test's consistency. A useful test is consistent over time. As an analogy, think of a bathroom scale. If it gives you one weight the first time you step on it, and a different weight when you step on it a moment later, it is not reliable. Similarly, if an IQ test yields a score of 95 for an individual today and 130 next week, it is not reliable. Reliability also can be a measure of a test's internal consistency. All of the items (questions) on a test should be measuring the same thing -- from a statistical standpoint, the items should correlate with each other. Good tests have reliability coefficients which range from a low of .65 to above .90 (the theoretical maximum is 1.00).
VALIDITY is a measure of a test's usefulness. Scores on the test should be related to some other behavior, reflective of personality, ability, or interest. For instance, a person who scores high on an IQ test would be expected to do well in school or on jobs requiring intelligence. A person who scores high on a scale of depression should be diagnosed as depressed by mental health professionals who assess him. A VALIDITY COEFFICIENT reflects the degree to which such relationships exist. Most tests have validity coefficients (correlations) of up to .30 with "real world" behavior. This is not a high correlation, and emphasizes the need to use tests in conjunction with other information. Relatively low correlations mean that some people may score high on a scale of schizophrenia without being schizophrenic and some people may score high on an IQ test and yet not do well in school. Correlations [as] high as .50 are seen between IQ and academic performance.
STANDARDIZATION is the process of trying out the test on a group of people to see the scores which are typically obtained. In this way, any test taker can make sense of his or her score by comparing it to typical scores. This standardization provides a mean (average) and standard deviation (spread) relative to a certain group. When an individual takes the test, she can determine how far above or below the average her score is, relative to the normative group. When evaluating a test, it is very important to determine how the normative group was selected. For instance, if everyone in the normative group took the test by logging into a website, you are probably being compared to a group which is very different from the general population.
8-pt step
Re: How to Construct a Psychological Test
Fr: http://www.psychologicaltesting.com/test_construction.htm, accessed 08 Oct 2008
Here are the basic steps to constructing a useful psychological test:
1) Determine the trait, ability, emotional state, disorder, interests, or attitude that you want to assess. Psychological tests can be created that measure --
Abilities, such as musical skill, writing skill, intelligence, or reading comprehension.
Personality Traits, such as extroversion, creativity, or deviousness, Disorders, such as anxiety, depression, psychotic thought disorder, Emotions, such as happiness and anger,
Attitudes, such as authoritarianism or prejudice,
Interests, such as career-related interests.
2) Decide how you want to measure the construct you selected. In general, the best measures sample the behavior of interest. For instances, if you want to determine how aggressive a person is, the best measure would be to provide a frustrating situation, and see whether the person reacts aggressively. It's not always practical or ethical to directly measure constructs, so instead, tests rely on a person's self-report of their behavior.
A number of other factors need to be considered. Should the test be written, or should it be administered orally? Should the responses be discrete (a rating scale, or Yes/No answers), or should it allow open-ended answers that can be reliably rated? Should the responses be oral, written, or nonverbal?
3) Does the construct that you want to measure have only one dimension, or can it be broken down into several dimensions? For instance, intelligence is usually considered multi-dimensional, consisting of several different verbal abilities and nonverbal abilities.
4) Once you've made decisions about the factors above, you can begin creating your test items. If the items are measuring a particular area of knowledge, then you will review textbooks or consult subject-matter experts in that area. If you are measuring a personality trait or emotional state, then the items should be consistent with a theory or agreed upon description of what you are measuring. It's generally best for several experts to generate items.
5) After generating items, it often makes sense to have experts rate the quality of the items, and to retain only the items with the highest ratings. The experts can also suggest revisions. If your items measure depression, the experts should be mental health professionals. If your items measure business skill, your experts should be business executives and managers.
6) Your test is then ready to be tested on a sample of people. Your sample should be a good cross-section of the people that you will want to compare test-takers to. After you administer your test to a sample of people:
-Determine the correlation between each item and the sum of the other items. If your test has subscales, do this separately for each subscale. Eliminate items that do not correlate well with the rest of their scale.
-Eliminate items that are too easy or too hard. If almost everyone agrees with an item or gets the correct answer, it is not a useful item.
-This procedure will maximize the test's internal consistency, one measure of reliability. You should calculate coefficient alpha. This statistic measures the degree to which a test scale measures a single construct, and the degree to which the test items are all measuring the same ability or trait. Alpha has a theoretical maximum of +1.00. A good test alpha is greater than .70.
7) The final test should be cross-validated on a new sample. During cross-validation, you can demonstrate test validity:
-You should be able to show that your test scores correlate with what they are supposed to correlate with. For instance, a test of math skill should yield higher scores for students with higher math grades. A test of depression should yield higher scores for people who have been diagnosed with Major Depression.
-Factor analysis can be used to demonstrate that the test subscales group together (inter-correlate) in the way that theory would predict.
8) When the test is cross-validated, you can also calculate normative data. You can calculate the mean (average) score for test-takers, and calculate the standard deviation to determine how spread out the scores are around the mean. These statistics are extremely useful, because now any individual's score can be compared to the scores of people in general.
If your test has subscales, you will find the mean and standard deviation for each subscale. It is also often useful to find separate normative data for different groups of potential test takers. Many tests have norms according to gender, ethnic group, and age.
Fr: http://www.psychologicaltesting.com/test_construction.htm, accessed 08 Oct 2008
Here are the basic steps to constructing a useful psychological test:
1) Determine the trait, ability, emotional state, disorder, interests, or attitude that you want to assess. Psychological tests can be created that measure --
Abilities, such as musical skill, writing skill, intelligence, or reading comprehension.
Personality Traits, such as extroversion, creativity, or deviousness, Disorders, such as anxiety, depression, psychotic thought disorder, Emotions, such as happiness and anger,
Attitudes, such as authoritarianism or prejudice,
Interests, such as career-related interests.
2) Decide how you want to measure the construct you selected. In general, the best measures sample the behavior of interest. For instances, if you want to determine how aggressive a person is, the best measure would be to provide a frustrating situation, and see whether the person reacts aggressively. It's not always practical or ethical to directly measure constructs, so instead, tests rely on a person's self-report of their behavior.
A number of other factors need to be considered. Should the test be written, or should it be administered orally? Should the responses be discrete (a rating scale, or Yes/No answers), or should it allow open-ended answers that can be reliably rated? Should the responses be oral, written, or nonverbal?
3) Does the construct that you want to measure have only one dimension, or can it be broken down into several dimensions? For instance, intelligence is usually considered multi-dimensional, consisting of several different verbal abilities and nonverbal abilities.
4) Once you've made decisions about the factors above, you can begin creating your test items. If the items are measuring a particular area of knowledge, then you will review textbooks or consult subject-matter experts in that area. If you are measuring a personality trait or emotional state, then the items should be consistent with a theory or agreed upon description of what you are measuring. It's generally best for several experts to generate items.
5) After generating items, it often makes sense to have experts rate the quality of the items, and to retain only the items with the highest ratings. The experts can also suggest revisions. If your items measure depression, the experts should be mental health professionals. If your items measure business skill, your experts should be business executives and managers.
6) Your test is then ready to be tested on a sample of people. Your sample should be a good cross-section of the people that you will want to compare test-takers to. After you administer your test to a sample of people:
-Determine the correlation between each item and the sum of the other items. If your test has subscales, do this separately for each subscale. Eliminate items that do not correlate well with the rest of their scale.
-Eliminate items that are too easy or too hard. If almost everyone agrees with an item or gets the correct answer, it is not a useful item.
-This procedure will maximize the test's internal consistency, one measure of reliability. You should calculate coefficient alpha. This statistic measures the degree to which a test scale measures a single construct, and the degree to which the test items are all measuring the same ability or trait. Alpha has a theoretical maximum of +1.00. A good test alpha is greater than .70.
7) The final test should be cross-validated on a new sample. During cross-validation, you can demonstrate test validity:
-You should be able to show that your test scores correlate with what they are supposed to correlate with. For instance, a test of math skill should yield higher scores for students with higher math grades. A test of depression should yield higher scores for people who have been diagnosed with Major Depression.
-Factor analysis can be used to demonstrate that the test subscales group together (inter-correlate) in the way that theory would predict.
8) When the test is cross-validated, you can also calculate normative data. You can calculate the mean (average) score for test-takers, and calculate the standard deviation to determine how spread out the scores are around the mean. These statistics are extremely useful, because now any individual's score can be compared to the scores of people in general.
If your test has subscales, you will find the mean and standard deviation for each subscale. It is also often useful to find separate normative data for different groups of potential test takers. Many tests have norms according to gender, ethnic group, and age.
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