The MMPI-2 Profile of Adults with Learning Disabilities in University and Rehabilitation Settings Noel Gregg, Cheri Hoy, Michael King, Carolyn Moreland, and Meera Jagota
The primary purpose of this study was to compare the personality profiles of adults with learning disabilities attending a large state university (8 females, 8 males) to those participating in training programs in a rehabilitation setting (8 females, 18 males), in an attempt to identify affective variables that should be considered in transitional and postsecondary program planning. A secondary purpose of the study was to compare the performance of two groups of adults with learning disabilities (i.e., university and rehabilitation) to a normative group of college students. The mean age for all subjects was between 20 and 23 years. Findings from the study indicated that the personality profiles of individuals with learning disabilities in either a rehabilitation setting or seeking a university degree are significantly different from those of the normative population of normally achieving college students. The rehabilitation group in this study demonstrated feelings of social isolation, poor self-concept, self-doubt, and extreme restlessness. Somewhat different profiles were seen with the university group as they indicated feelings of fear, obsessive thoughts, lack of self-confidence, self-doubt, and extreme self-criticism. Both groups demonstrated profiles of individuals under extreme short- and long-term stress leading to anxiety. The study also reviewed the relevance and appropriateness of using the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) that will have direct application for the assessment and intervention of adults with learning disabilities either in a rehabilitation setting or seeking a university degree.
R
esearchers have noted that students with learning disabilities (LD) have consistently been described as having frail ego structures (Gaddes, 1985), poor interpersonal skills (La Greca, 1987), and negative self-concept (Wright & Stimmel, 1984). Others have found that children with specific learning disabilities exhibit increased levels of anxiety, withdrawal, depression, and low selfesteem when compared to nonhandicapped children (Eliason & Richman, 1988; McConaughy, 1986; McConaughy & Ritter, 1986; Rosenthal, 1973). Researchers have also documented that, compared to their normally achieving peers, children with specific
learning disabilities are less well liked and more likely to be rejected by others (Bruininks, 1978; Bryan, 1976; Garrett & Crump, 1980; Gresham & Reschly, 1986; La Greca & Stone, 1990; Morrison, 1981; Stone & La Greca, 1990). Behavioral observations reveal that students with learning disabilities receive more negative messages from their peers and are perceived as less socially skillful (La Greca, 1987; Vaughn & La Greca, 1988). Recent research (La Greca & Stone, 1990) has examined the relationship between achievement and learning disabilities in a study of children's social status, self-esteem, and behavioral functioning. However, La Greca and Stone conclude that JOURNAL OF LEARNING DISABILITIES VOLUME 25, NUMBER 6, JUNE/JULY 1992 Downloaded from ldx.sagepub.com UNIVERSITE LAVAL on July 2, 2015 PAGES at386-395
achievement alone cannot account for the poor performance of students with LD with respect to peer ratings of acceptance and self-perceptions. Recently, proposed definitions have begun to acknowledge the lifelong impact of the condition of learning disabilities on social competence and social skill attainment (Interagency Committee on Learning Disabilities, 1987; Learning Disabilities Association, 1986). Johnson and Blalock (1987) found that difficulties with self-concept and social acceptance continue to be problems for adults with learning disabilities. While few would argue that growing up with a specific learning disability places one at risk for socialemotional difficulties, information on the impact of the disability on personality structure is weak and inconsistent. Unfortunately, the affective, cognitive, and academic abilities of individuals with learning disabilities are quite often treated as separate domains having very little impact on each other. Yet, personality is basic to cognitive development and is essential to the learning process (Gaddes, 1985). The question of whether there exists a personality profile characteristic of individuals with learning disabilities is an interesting one. Similar questions have been raised regarding characteristic personality profiles of other clinical groups and groups of people in specific occupations. Research on the personal-
387
VOLUME 25, NUMBER 6, JUNE/JULY 1992
ity structure of individuals growing up with specific learning disabilities requires greater attention from professionals. Understanding the impact of specific learning disabilities on an individual's different life stages—and hence personality structure—will aid in developing more appropriate academic, vocational, and social competencies. The increase of individuals identified as demonstrating learning disabilities in secondary settings has resulted in concern over effective transitional competencies for students that would lead to competitive employment. Professionals working with individuals with learning disabilities have not been successful in identifying and teaching the competencies necessary for future success and satisfaction in the world of work. This problem is particularly evident when one considers the lack of success professionals appear to have in helping adults with learning disabilities become more independent. Unfortunately, many professionals working with individuals possessing special needs on employment skills often focus on program and curricula activities and ignore the role of evaluation in developing career goals (Hursch, 1989). Evaluation of cognitive ability, affective functioning, style of learning, academic performance, vocational abilities, and interests must be considered in developing effective prosocial skill plans for adults with learning disabilities (Gregg & Hoy, 1990). In addition, careful consideration must be given to the selection of evaluation tools that will provide professionals with the most efficient and effective information for planning career goals.
Minnesota Multiphasic Personality Inventory-2 The Minnesota Multiphasic Personality Inventory (Hathaway & McKinley, 1940, 1942) has historically been one of the most frequently used psychological tests across rehabilitation, psychiatric, medical, college, school,
prison, and industry settings (Lubin, Larsen, Matarazzo, & Seever, 1985). Practitioners and researchers have for years been concerned about the need for an MMPI revision, as the norms have not been updated from the first publication in the 1940s. Fortunately, a revision of the MMPI has recently become available to professionals. The MMPI-2 (Butcher, Dahlstrom, Graham, Tellegren, & Kaemmer, 1989) eliminates the problem of inappropriate norms, provides new T scores that are relevant for contemporary use, and allows the application of previous research data on the MMPI clinical scales. Research documenting the application and relevance of the MMPI-2 scales with special needs populations is scant, due to its recency. Researchers have investigated some clinical groups, such as inpatient psychiatric samples (Graham & Butcher, 1988), chronic pain patients (Keller & Butcher, 1990), inpatient alcohol and drug abusers (McKenna & Butcher, 1987), couples in marital counseling (Hjemboe & Butcher, in press), and childabusing families (Egeland, Erickson, Butcher, & Ben-Porath, in press), as well as special norm groups, which include military personnel (Butcher et al., 1990), college students (Butcher, Graham, Dahlstrom, & Bowman, 1990), and older subjects (Butcher, Aldwin, Levenson, Ben-Porath, Spiro, & Bosse, in press). What is clearly missing in the current literature is the application of the MMPI-2 scales for populations with developmental disabilities. Developmental issues, like those of identity formation and cognitive development, raise the question of whether the population of adults with specific learning disabilities would respond to the MMPI-2 differently than normally achieving adults. Stephens (1988) discussed the limitations of many of the self-report inventories investigating depression, anxiety, and locus of control with individuals with specific learning disabilities. She pointed to the impact of attention, oral language, and reading problem skills on accurate in-
Downloaded from ldx.sagepub.com at UNIVERSITE LAVAL on July 2, 2015
terpretations of the profiles attained from such measurement tools. Certainly, psychologists need to consider the developmental level, reading and language skills, motivation, attentional abilities, and experiences of their clients before deciding to use a selfreport measure like the MMPI-2. The MMPI-2 manual suggests that an eighth-grade reading comprehension score is necessary for independent reading (Butcher et al., 1989). The primary purpose of the present study was to compare the personality profiles of adults with learning disabilities across postsecondary settings (i.e., university or rehabilitation) in an attempt to identify affective variables that should be considered in transitional or postsecondary program planning. A secondary purpose of the study was to compare the performance of two groups of adults with learning disabilities (i.e., university and rehabilitation) to a normative group of college students. The study also reviewed the relevance and appropriateness of using the MMPI-2 for the assessment and intervention of adults with learning disabilities either in a rehabilitation setting or seeking a university degree.
Method Subjects Rehabilitation Population. Subjects selected for this group were all clients at Roosevelt Warm Springs Institute for Rehabilitation, Warm Springs, Georgia, with documented histories of learning disabilities. All subjects were reevaluated with psychological and psychoeducational assessment tools to document the learning disabilities. Only subjects that fit the following criteria were included in the study: (1) evidence of academic underachievement, defined by results from one or more areas of achievement as measured by tests such as the Woodcock-Johnson Psycho-Educational Tests of Achievement-Revised, Standard Battery (Woodcock & Johnson,
388
JOURNAL OF LEARNING DISABILITIES
1989), being at least IV3 standard devi- Clinic during the school year 1989-91. individual. No diagnoses were made ations below the individual's Wechs- The first 16 students diagnosed as on the basis of a single test score or disler Adult Intelligence Scale-Revised demonstrating a specific learning dis- crepancy measure; rather, they were (WAIS-R) (Wechsler, 1981) Full Scale ability were contacted and asked to based on patterns of problems and standard score; (2) evidence of cogni- complete the MMPI-2 for research pur- errors. The same four criteria applied tive processing deficits, defined by poses. All 16 agreed to this request. to the rehabilitation group described results from one or more areas of cog- Each of these students, seeking eligi- above were also applied to the univernitive processing as measured by a var- bility for learning disabilities support sity group in determining eligibility. iety of standardized cognitive instru- services at the University of Georgia, Two of the 16 subjects were black and ments, such as the Woodcock-Johnson had been admitted to the university the rest were white. Fourteen of the Psycho-Educational Test of Cognitive under regular admissions procedures. subjects came from middle and workAbility-Revised, Standard Battery Each subject's diagnosis as learning ing class families and two came from (Woodcock & Johnson, 1989) (designed disabled had been confirmed during a upper middle class families. to assess cognitive processing areas of 2-day psychoeducational assessment at perception, reasoning, symbolic rep- the university's Learning Disabilities Procedure resentation, and memory), being at Adult Clinic. least IV3 standard deviations below The MMPI-2 was administered in The presence of learning disabilities one of the individual's WAIS-R scale was determined by a diagnostic staff group testing sessions with six clients scores (VIQ, PIQ, FSIQ); (3) no evi- of learning disabilities specialists, clin- in each group, lasting about 3 to 5 dence of sensory impairment or men- ical psychologists, and graduate stu- hours, with periodic breaks for both tal retardation as defined by detailed dent clinicians. Clinical judgment was the university and rehabilitation background information (i.e., visual used to interpret test results, as well as groups. A testing proctor distributed and audiological reports, school tran- to analyze error responses, writing materials and answered individually scripts, birth and educational histories, samples, and data obtained from infor- any questions the subjects might have. prior psychological and educational mal assessment measures. Quantita- All subjects completed a computer anevaluations); and (4) no evidence of tive data included results from stan- swer sheet. Ten of the 26 subjects in a primary psychiatric disorder as dardized tests and informal measures. the rehabilitation group and 4 of the evaluated by a structured psychiat- Qualitative data included information university group had documented ric interview used for DSM-III-R gathered from case histories, inter- reading levels lower than eighth grade (American Psychiatric Association, views, and previous records that con- and were administered the tape ver1987) diagnosis that was administered firmed the chronicity of learning prob- sion of the MMPI-2 during individual individually by a clinical psychologist. lems. Clinical judgment, as well as sessions supervised by a test proctor. Only adults with WAIS-R Full Scale quantitative and qualitative data, was All data were computer scored as a scores of 80 or above were included in incorporated in a careful study of the reliability control. the study. Twenty-six adults from the rehabilitation setting met this criteria and were included in this study. Twenty of the subjects were white and six TABLE 1 were black. Twenty-three subjects Data for Subjects Descriptive came from middle and working class families, and three came from upper Rehabilitation University middle class families. Information Variable Mean SD Mean SD gathered and reported for each client in the study is consistent with the Age 23.65 14.56 20.06 5.59 marker variable system that Keogh PPVT-R 84.69 103.07 12.23 15.89 (1983) suggested researchers in the WAIS-R Full Scale 87.23 107.27 12.24 5.85 area of learning disabilities utilize Verbal 87.23 8.37 106.27 10.26 to describe study populations. See Performance 88.77 9.76 106.40 14.25 Table 1 for descriptive data on the WJPB-R subjects. Broad Cognitive 83.39 13.89 99.00 12.22 University Population. Subjects selected for the study were college students evaluated by the University of Georgia's Learning Disabilities Adult
Reading Achievement Math Achievement
87.00 88.04
10.57 12.20
104.92 100.90
12.29 14.84
Note. PPVT-R = Peabody Picture Vocabulary Test-Revised (Dunn & Dunn, 1981); WAIS-R = Wechsler Adult Intelligence Scale-Revised (Wechsler, 1981); WJPB-R = Woodcock Johnson Psycho-Educational Battery-Revised (Woodcock & Johnson, 1989).
Downloaded from ldx.sagepub.com at UNIVERSITE LAVAL on July 2, 2015
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VOLUME 25, NUMBER 6, JUNE/JULY 1992
Validity of Scores
ity scales (Tellegen, 1988). Unlike the L, F, and K scales, the VRIN and TRIN scales do not measure item content; rather, they provide an index of the tendency of a subject to respond to items in ways that are inconsistent or contradictory. All subjects selected were required to score within the low to moderate range on both the VRIN and TRIN scales. Graham (1987) and Greene (1989) provided further discussions about the patterns formed by these validity scales. Because these indicators are at the experimental stage, interpretation must be made cautiously. Butcher et al. (1989) suggested that extreme values in the normative sample be used as clinical indicators: VRIN raw score of 13 or greater and TRIN raw score of 5 or less, or of 13 or greater. All subjects selected were required to have valid VRIN and TRIN scales.
homogeneity of variances was tested first. One clinical scale variable (hysteria) and three content scale variables (cynicism, antisocial practices, negative treatment indicators) failed to meet the assumption of homogeneity of variances. For these four variables, a t test adjusted for unequal variances was used. For all other variables, a standard t test was used to examine group differences. The means, standard deviations, and t values for the clinical scale variables appear in Table 2. Significant group differences were found for four variables at the .05 level. The university subjects had significantly higher T scores than the rehabilitation subjects on the hysteria variable. However, rehabilitation subjects had significantly higher T scores than the university subjects on the variables of schizophrenia and mania. No significant differences were found on any of the other clinical scale variables. The means, standard deviations, and t values for the content scale variables appear in Table 3. Using a .05 level of significance, group differences were found on five of the variables: depression, cynicism, antisocial practices, work interference, and negative treatment indicators. For all five variables, rehabilitation subjects had significantly higher T scores than university sub-
The MMPI-2 validity indicators can be used either in isolation or in combination to determine acceptability of any profile (Butcher et al., 1989). One of these indicators, the Cannot Say score, provides a count of the number of items either unanswered or marked both true and false by the test taker. Another indicator, the L scale, serves as an index of the likelihood that a person has spoiled the test protocol by a specific style of responding to the questions. Subjects selected for this study were required to have Cannot Say scores and L scales within the low to moderate range. The F (Infrequency) scale identifies subjects answering the questions in a random manner. A T score of 90 or higher is certainly of questionable validity. A new validity measure, the F(B) scale or back side F scale, has been incorporated in the MMPI-2 to identify possible deviant responding to items Results located toward the end of the questionnaire. Valid F(B) T scores should be The MMPI-2 contains several difbelow T=70. None of the subjects had ferent scales. The scales of the most F scale scores greater than 89 or F(B) interest for this study were the clinscale T scores greater than 69. How- ical scales with 10 variables, the conever, the mean F scale score for the re- tent scales with 15 variables, and the habilitation group was 65, with an F(B) traditional scales with 10 variables. mean of 59, while the university group Because the groups had unequal numF mean was 56, with an F(B) mean of bers of subjects (rehabilitation = 26, 54. The high F(B) T scale scores of the university = 16), the assumption of rehabilitation group indicate that the subjects generally tended to answer randomly toward the end of the test. TABLE 2 Attention, language, and reading difficulties could easily be contributing to T Scores for the MMPI-2 Clinical Scales and t Test Results these high scale scores. The K (Correction) scale is a validity indicator that identifies characteristics that many individuals prefer to deny about themselves and their families but that others view as positive attributes. The K scale makes allowances for the impact of test-taking orientations of the scores of the component scales. All subjects were required to be within the normal range on the K scale. The Variable Response Inconsistency (VRIN) and the True Response Inconsistency (TRIN)' scales are new valid-
Rehabilitation
University
Variable
Mean
SD
Mean
SD
t
Hypochondriasis (Hs) Depression (D) Hysteria (Hy) + Psychopathic Deviate (Pd) Paranoia (Pa) Psychasthemia (Pt) Schizophrenia (Sc) Mania (Ma) Social Introversion (Si)
54.42 54.53 48.26
13.17 10.14 12.95
52.81 55.62 55.00
10.65 14.55 7.78
.41 -.29 -2.10*
60.26 62.15 62.30 68.73 66.07 56.61
14.85 16.65 10.14 11.98 14.16 7.39
56.37 59.06 66.50 59.68 54.43 51.39
12.44 12.21 11.49 12.13 9.25 9.51
.88 .64 -.65 2.36* 2.91* 1.78
Note. + = unequal variances, adjusted t test used. * p
The primary purpose of this study was to compare the personality profiles of adults with learning disabilities attending a large state university (8 females, 8 males) to those participating in training programs in a rehabilitation setting (8 females, 18 males), in an attempt to identify affective variables that should be considered in transitional and postsecondary program planning. A secondary purpose of the study was to compare the performance of two groups of adults with learning disabilities (i.e., university and rehabilitation) to a normative group of college students. The mean age for all subjects was between 20 and 23 years. Findings from the study indicated that the personality profiles of individuals with learning disabilities in either a rehabilitation setting or seeking a university degree are significantly different from those of the normative population of normally achieving college students. The rehabilitation group in this study demonstrated feelings of social isolation, poor self-concept, self-doubt, and extreme restlessness. Somewhat different profiles were seen with the university group as they indicated feelings of fear, obsessive thoughts, lack of self-confidence, self-doubt, and extreme self-criticism. Both groups demonstrated profiles of individuals under extreme short- and long-term stress leading to anxiety. The study also reviewed the relevance and appropriateness of using the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) that will have direct application for the assessment and intervention of adults with learning disabilities either in a rehabilitation setting or seeking a university degree.
R
esearchers have noted that students with learning disabilities (LD) have consistently been described as having frail ego structures (Gaddes, 1985), poor interpersonal skills (La Greca, 1987), and negative self-concept (Wright & Stimmel, 1984). Others have found that children with specific learning disabilities exhibit increased levels of anxiety, withdrawal, depression, and low selfesteem when compared to nonhandicapped children (Eliason & Richman, 1988; McConaughy, 1986; McConaughy & Ritter, 1986; Rosenthal, 1973). Researchers have also documented that, compared to their normally achieving peers, children with specific
learning disabilities are less well liked and more likely to be rejected by others (Bruininks, 1978; Bryan, 1976; Garrett & Crump, 1980; Gresham & Reschly, 1986; La Greca & Stone, 1990; Morrison, 1981; Stone & La Greca, 1990). Behavioral observations reveal that students with learning disabilities receive more negative messages from their peers and are perceived as less socially skillful (La Greca, 1987; Vaughn & La Greca, 1988). Recent research (La Greca & Stone, 1990) has examined the relationship between achievement and learning disabilities in a study of children's social status, self-esteem, and behavioral functioning. However, La Greca and Stone conclude that JOURNAL OF LEARNING DISABILITIES VOLUME 25, NUMBER 6, JUNE/JULY 1992 Downloaded from ldx.sagepub.com UNIVERSITE LAVAL on July 2, 2015 PAGES at386-395
achievement alone cannot account for the poor performance of students with LD with respect to peer ratings of acceptance and self-perceptions. Recently, proposed definitions have begun to acknowledge the lifelong impact of the condition of learning disabilities on social competence and social skill attainment (Interagency Committee on Learning Disabilities, 1987; Learning Disabilities Association, 1986). Johnson and Blalock (1987) found that difficulties with self-concept and social acceptance continue to be problems for adults with learning disabilities. While few would argue that growing up with a specific learning disability places one at risk for socialemotional difficulties, information on the impact of the disability on personality structure is weak and inconsistent. Unfortunately, the affective, cognitive, and academic abilities of individuals with learning disabilities are quite often treated as separate domains having very little impact on each other. Yet, personality is basic to cognitive development and is essential to the learning process (Gaddes, 1985). The question of whether there exists a personality profile characteristic of individuals with learning disabilities is an interesting one. Similar questions have been raised regarding characteristic personality profiles of other clinical groups and groups of people in specific occupations. Research on the personal-
387
VOLUME 25, NUMBER 6, JUNE/JULY 1992
ity structure of individuals growing up with specific learning disabilities requires greater attention from professionals. Understanding the impact of specific learning disabilities on an individual's different life stages—and hence personality structure—will aid in developing more appropriate academic, vocational, and social competencies. The increase of individuals identified as demonstrating learning disabilities in secondary settings has resulted in concern over effective transitional competencies for students that would lead to competitive employment. Professionals working with individuals with learning disabilities have not been successful in identifying and teaching the competencies necessary for future success and satisfaction in the world of work. This problem is particularly evident when one considers the lack of success professionals appear to have in helping adults with learning disabilities become more independent. Unfortunately, many professionals working with individuals possessing special needs on employment skills often focus on program and curricula activities and ignore the role of evaluation in developing career goals (Hursch, 1989). Evaluation of cognitive ability, affective functioning, style of learning, academic performance, vocational abilities, and interests must be considered in developing effective prosocial skill plans for adults with learning disabilities (Gregg & Hoy, 1990). In addition, careful consideration must be given to the selection of evaluation tools that will provide professionals with the most efficient and effective information for planning career goals.
Minnesota Multiphasic Personality Inventory-2 The Minnesota Multiphasic Personality Inventory (Hathaway & McKinley, 1940, 1942) has historically been one of the most frequently used psychological tests across rehabilitation, psychiatric, medical, college, school,
prison, and industry settings (Lubin, Larsen, Matarazzo, & Seever, 1985). Practitioners and researchers have for years been concerned about the need for an MMPI revision, as the norms have not been updated from the first publication in the 1940s. Fortunately, a revision of the MMPI has recently become available to professionals. The MMPI-2 (Butcher, Dahlstrom, Graham, Tellegren, & Kaemmer, 1989) eliminates the problem of inappropriate norms, provides new T scores that are relevant for contemporary use, and allows the application of previous research data on the MMPI clinical scales. Research documenting the application and relevance of the MMPI-2 scales with special needs populations is scant, due to its recency. Researchers have investigated some clinical groups, such as inpatient psychiatric samples (Graham & Butcher, 1988), chronic pain patients (Keller & Butcher, 1990), inpatient alcohol and drug abusers (McKenna & Butcher, 1987), couples in marital counseling (Hjemboe & Butcher, in press), and childabusing families (Egeland, Erickson, Butcher, & Ben-Porath, in press), as well as special norm groups, which include military personnel (Butcher et al., 1990), college students (Butcher, Graham, Dahlstrom, & Bowman, 1990), and older subjects (Butcher, Aldwin, Levenson, Ben-Porath, Spiro, & Bosse, in press). What is clearly missing in the current literature is the application of the MMPI-2 scales for populations with developmental disabilities. Developmental issues, like those of identity formation and cognitive development, raise the question of whether the population of adults with specific learning disabilities would respond to the MMPI-2 differently than normally achieving adults. Stephens (1988) discussed the limitations of many of the self-report inventories investigating depression, anxiety, and locus of control with individuals with specific learning disabilities. She pointed to the impact of attention, oral language, and reading problem skills on accurate in-
Downloaded from ldx.sagepub.com at UNIVERSITE LAVAL on July 2, 2015
terpretations of the profiles attained from such measurement tools. Certainly, psychologists need to consider the developmental level, reading and language skills, motivation, attentional abilities, and experiences of their clients before deciding to use a selfreport measure like the MMPI-2. The MMPI-2 manual suggests that an eighth-grade reading comprehension score is necessary for independent reading (Butcher et al., 1989). The primary purpose of the present study was to compare the personality profiles of adults with learning disabilities across postsecondary settings (i.e., university or rehabilitation) in an attempt to identify affective variables that should be considered in transitional or postsecondary program planning. A secondary purpose of the study was to compare the performance of two groups of adults with learning disabilities (i.e., university and rehabilitation) to a normative group of college students. The study also reviewed the relevance and appropriateness of using the MMPI-2 for the assessment and intervention of adults with learning disabilities either in a rehabilitation setting or seeking a university degree.
Method Subjects Rehabilitation Population. Subjects selected for this group were all clients at Roosevelt Warm Springs Institute for Rehabilitation, Warm Springs, Georgia, with documented histories of learning disabilities. All subjects were reevaluated with psychological and psychoeducational assessment tools to document the learning disabilities. Only subjects that fit the following criteria were included in the study: (1) evidence of academic underachievement, defined by results from one or more areas of achievement as measured by tests such as the Woodcock-Johnson Psycho-Educational Tests of Achievement-Revised, Standard Battery (Woodcock & Johnson,
388
JOURNAL OF LEARNING DISABILITIES
1989), being at least IV3 standard devi- Clinic during the school year 1989-91. individual. No diagnoses were made ations below the individual's Wechs- The first 16 students diagnosed as on the basis of a single test score or disler Adult Intelligence Scale-Revised demonstrating a specific learning dis- crepancy measure; rather, they were (WAIS-R) (Wechsler, 1981) Full Scale ability were contacted and asked to based on patterns of problems and standard score; (2) evidence of cogni- complete the MMPI-2 for research pur- errors. The same four criteria applied tive processing deficits, defined by poses. All 16 agreed to this request. to the rehabilitation group described results from one or more areas of cog- Each of these students, seeking eligi- above were also applied to the univernitive processing as measured by a var- bility for learning disabilities support sity group in determining eligibility. iety of standardized cognitive instru- services at the University of Georgia, Two of the 16 subjects were black and ments, such as the Woodcock-Johnson had been admitted to the university the rest were white. Fourteen of the Psycho-Educational Test of Cognitive under regular admissions procedures. subjects came from middle and workAbility-Revised, Standard Battery Each subject's diagnosis as learning ing class families and two came from (Woodcock & Johnson, 1989) (designed disabled had been confirmed during a upper middle class families. to assess cognitive processing areas of 2-day psychoeducational assessment at perception, reasoning, symbolic rep- the university's Learning Disabilities Procedure resentation, and memory), being at Adult Clinic. least IV3 standard deviations below The MMPI-2 was administered in The presence of learning disabilities one of the individual's WAIS-R scale was determined by a diagnostic staff group testing sessions with six clients scores (VIQ, PIQ, FSIQ); (3) no evi- of learning disabilities specialists, clin- in each group, lasting about 3 to 5 dence of sensory impairment or men- ical psychologists, and graduate stu- hours, with periodic breaks for both tal retardation as defined by detailed dent clinicians. Clinical judgment was the university and rehabilitation background information (i.e., visual used to interpret test results, as well as groups. A testing proctor distributed and audiological reports, school tran- to analyze error responses, writing materials and answered individually scripts, birth and educational histories, samples, and data obtained from infor- any questions the subjects might have. prior psychological and educational mal assessment measures. Quantita- All subjects completed a computer anevaluations); and (4) no evidence of tive data included results from stan- swer sheet. Ten of the 26 subjects in a primary psychiatric disorder as dardized tests and informal measures. the rehabilitation group and 4 of the evaluated by a structured psychiat- Qualitative data included information university group had documented ric interview used for DSM-III-R gathered from case histories, inter- reading levels lower than eighth grade (American Psychiatric Association, views, and previous records that con- and were administered the tape ver1987) diagnosis that was administered firmed the chronicity of learning prob- sion of the MMPI-2 during individual individually by a clinical psychologist. lems. Clinical judgment, as well as sessions supervised by a test proctor. Only adults with WAIS-R Full Scale quantitative and qualitative data, was All data were computer scored as a scores of 80 or above were included in incorporated in a careful study of the reliability control. the study. Twenty-six adults from the rehabilitation setting met this criteria and were included in this study. Twenty of the subjects were white and six TABLE 1 were black. Twenty-three subjects Data for Subjects Descriptive came from middle and working class families, and three came from upper Rehabilitation University middle class families. Information Variable Mean SD Mean SD gathered and reported for each client in the study is consistent with the Age 23.65 14.56 20.06 5.59 marker variable system that Keogh PPVT-R 84.69 103.07 12.23 15.89 (1983) suggested researchers in the WAIS-R Full Scale 87.23 107.27 12.24 5.85 area of learning disabilities utilize Verbal 87.23 8.37 106.27 10.26 to describe study populations. See Performance 88.77 9.76 106.40 14.25 Table 1 for descriptive data on the WJPB-R subjects. Broad Cognitive 83.39 13.89 99.00 12.22 University Population. Subjects selected for the study were college students evaluated by the University of Georgia's Learning Disabilities Adult
Reading Achievement Math Achievement
87.00 88.04
10.57 12.20
104.92 100.90
12.29 14.84
Note. PPVT-R = Peabody Picture Vocabulary Test-Revised (Dunn & Dunn, 1981); WAIS-R = Wechsler Adult Intelligence Scale-Revised (Wechsler, 1981); WJPB-R = Woodcock Johnson Psycho-Educational Battery-Revised (Woodcock & Johnson, 1989).
Downloaded from ldx.sagepub.com at UNIVERSITE LAVAL on July 2, 2015
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VOLUME 25, NUMBER 6, JUNE/JULY 1992
Validity of Scores
ity scales (Tellegen, 1988). Unlike the L, F, and K scales, the VRIN and TRIN scales do not measure item content; rather, they provide an index of the tendency of a subject to respond to items in ways that are inconsistent or contradictory. All subjects selected were required to score within the low to moderate range on both the VRIN and TRIN scales. Graham (1987) and Greene (1989) provided further discussions about the patterns formed by these validity scales. Because these indicators are at the experimental stage, interpretation must be made cautiously. Butcher et al. (1989) suggested that extreme values in the normative sample be used as clinical indicators: VRIN raw score of 13 or greater and TRIN raw score of 5 or less, or of 13 or greater. All subjects selected were required to have valid VRIN and TRIN scales.
homogeneity of variances was tested first. One clinical scale variable (hysteria) and three content scale variables (cynicism, antisocial practices, negative treatment indicators) failed to meet the assumption of homogeneity of variances. For these four variables, a t test adjusted for unequal variances was used. For all other variables, a standard t test was used to examine group differences. The means, standard deviations, and t values for the clinical scale variables appear in Table 2. Significant group differences were found for four variables at the .05 level. The university subjects had significantly higher T scores than the rehabilitation subjects on the hysteria variable. However, rehabilitation subjects had significantly higher T scores than the university subjects on the variables of schizophrenia and mania. No significant differences were found on any of the other clinical scale variables. The means, standard deviations, and t values for the content scale variables appear in Table 3. Using a .05 level of significance, group differences were found on five of the variables: depression, cynicism, antisocial practices, work interference, and negative treatment indicators. For all five variables, rehabilitation subjects had significantly higher T scores than university sub-
The MMPI-2 validity indicators can be used either in isolation or in combination to determine acceptability of any profile (Butcher et al., 1989). One of these indicators, the Cannot Say score, provides a count of the number of items either unanswered or marked both true and false by the test taker. Another indicator, the L scale, serves as an index of the likelihood that a person has spoiled the test protocol by a specific style of responding to the questions. Subjects selected for this study were required to have Cannot Say scores and L scales within the low to moderate range. The F (Infrequency) scale identifies subjects answering the questions in a random manner. A T score of 90 or higher is certainly of questionable validity. A new validity measure, the F(B) scale or back side F scale, has been incorporated in the MMPI-2 to identify possible deviant responding to items Results located toward the end of the questionnaire. Valid F(B) T scores should be The MMPI-2 contains several difbelow T=70. None of the subjects had ferent scales. The scales of the most F scale scores greater than 89 or F(B) interest for this study were the clinscale T scores greater than 69. How- ical scales with 10 variables, the conever, the mean F scale score for the re- tent scales with 15 variables, and the habilitation group was 65, with an F(B) traditional scales with 10 variables. mean of 59, while the university group Because the groups had unequal numF mean was 56, with an F(B) mean of bers of subjects (rehabilitation = 26, 54. The high F(B) T scale scores of the university = 16), the assumption of rehabilitation group indicate that the subjects generally tended to answer randomly toward the end of the test. TABLE 2 Attention, language, and reading difficulties could easily be contributing to T Scores for the MMPI-2 Clinical Scales and t Test Results these high scale scores. The K (Correction) scale is a validity indicator that identifies characteristics that many individuals prefer to deny about themselves and their families but that others view as positive attributes. The K scale makes allowances for the impact of test-taking orientations of the scores of the component scales. All subjects were required to be within the normal range on the K scale. The Variable Response Inconsistency (VRIN) and the True Response Inconsistency (TRIN)' scales are new valid-
Rehabilitation
University
Variable
Mean
SD
Mean
SD
t
Hypochondriasis (Hs) Depression (D) Hysteria (Hy) + Psychopathic Deviate (Pd) Paranoia (Pa) Psychasthemia (Pt) Schizophrenia (Sc) Mania (Ma) Social Introversion (Si)
54.42 54.53 48.26
13.17 10.14 12.95
52.81 55.62 55.00
10.65 14.55 7.78
.41 -.29 -2.10*
60.26 62.15 62.30 68.73 66.07 56.61
14.85 16.65 10.14 11.98 14.16 7.39
56.37 59.06 66.50 59.68 54.43 51.39
12.44 12.21 11.49 12.13 9.25 9.51
.88 .64 -.65 2.36* 2.91* 1.78
Note. + = unequal variances, adjusted t test used. * p
