Psychological Reports, 1991, 69, 279-282.
O Psychological Reports 1991
PRINCIPAL COMPONENTS ANALYSIS O F T H E PSYCHOLOGICAL SCREENING INVENTORY IN A SAMPLE O F SUBSTANCE ABUSERS ' GARY E. DUNN, ANTHONY M. PAOLO, JOSEPH J. RYAN
Dwight D. Eisenhower Department of Veterans Affairs Medical Center, LPavenworth, Kansar Summary.-A principal components analysis of responses to the Psychological Screening Inventory from a sample of substance abusers was conducted. Subjects were 153 inpatients admitted to a midwestern program for chemical dependency treatment. Means for age and education were 28.0 yr. (SD = 8.1) and 11.4 (SD= 1.81, respectively. Analysis indicated that a two-factor solution best described these data. Factor 1 reflected over-all maladiustment. while Factor 2 was a measure of extroversion. Clinical utility of the inventory was discussed.
Patients in alcohol and substance abuse programs should be evaluated for the presence of significant psychopathology. Since it is not always feasible to use lengthy psychological measures, brief personality screening instruments may offer cost effective methods of obtaining useful clinical information. Prior to using such measures, however, their validity should be established. Unfortunately, clinical use of the screening devices often tends to precede such evaluations. The Psychological Screening Inventory (Lanyon, 1973), which is frequently used with substance abusers, is a brief instrument designed to identify persons who are in need of more intensive psychological evaluation. The inventory consists of 130 true-false items which yield five scales: Alienation (Al), Social Nonconformity (Sn), Discomfort (Di), Expression (Ex), and Defensiveness (De). The validity of these dimensions was assessed by Lanyon and associates using a sample of 800 normal persons of 16 to 60 years of age. A series of item factor analyses generally supported the five subscales (Lanyon, Johnson, & Overall, 1974; Lanyon, 1978; Overall, Johnson, & Lanyon, 1974). Conversely, when Johnson and Overall (1973) investigated the factor structure of the items using a sample of 150 undergraduate psychology students, they found that three relatively uncorrelated factors best described the data (Introversion, Social Maladjustment, and Emotional Maladjustment). They concluded that, although a general correspondence between the three-factor solution and certain dimensions was apparent, it was not possible to define a five-factor solution that directly related to the five subscales.
'Requests for reprints should be addressed to Gary Durn, Ph.D., Psychology Service (IlbB), Dwight D. Eisenhower VAMC, Leavenworth, KS 66048.
280
G. E. D U N N , ETAL.
Although item factor analyses are of some psychometric interest, the clinical utility of most instruments rests on interpretation of the various scales, either individually or in concert. Factor solutions of these subscales may provide useful clinical interpretive hypotheses. Further, a principal components analysis has not been conducted with substance abusers, so this study is an initial attempt to respond to these issues. Subjects Subjects were 153 inpatients admitted to a midwestern chemical dependency treatment program. Means for age and education were 28.0 yr. (SD = 8.1) and 11.4 (SD = 1.8), respectively. Average T scores for the subscales were 56.4 (SD = 11.7) for Alienation, 60.7 (SD = 9.8) for Social Nonconformity, 53.2 (SD = 12.0) for Discomfort, 48.3 (SD = 8.2) for Expression, and 48.0 (SD = 10.0) for Defensiveness. There were 123 men and 30 women. Of the total sample, 71% were Caucasian, 25% were African-American, and the remaining 4% were Hispanic or Native American. Procedure As part of the standard intake assessment, all persons admitted into the treatment program during a six-month period completed the inventory. Principal components analysis (i.e., unity in the diagonal) followed by varimax rotation for the correlation matrix of the subscales was conducted to select the linear combinations that account for most of the total variance (Dillon & Goldstein, 1984). The number of factors to be retained was determined by Kaiser's eigenvalue > one (Hollenbeck, 1972). AU analyses were conducted using SPSS/PC + Version 3. RESULTSAND DISCUSSION Table 1 provides the factor solution for the subscales. As can be seen, the first factor consists of Discomfort, Social Nonconformity, Defensiveness, and ALienation scales and accounts for 43.9% of the variance. The second factor is made up of the Expression scale and accounts for 22.3% of the variance. The first factor appears to reflect over-all maladjustment and the second factor reflects extroversion. Although the results do not support the five scales developed by Lanyon (1978), they are generally consistent with the results reported by Johnson and Overall (1973). The current two-factor solution is U e l y a function of the population used. Graham and Strenger (1988), in a review of the characteristics of alcoholics, found significant elevations on MMPI scales that measure depression
'Data were collected while the first author was at Parallax Program Incorporated, Wichita,
Kansas.
FACTOR ANALYSIS O F THE PSI TABLE 1 OF THE SUBSCALES FACTOR STRUCTURE Scale
Factor I
Factor I1
Discomfort Social Nonconformity Defensiveness Alienation Ex~ression
.82 .81 -.68 .65 .03
-.29 .21 -.I1 -.37 .92
(Scale 2), anxiety (Scale 7), antisocial traits (Scales 4 and 9), and disordered thinking (Scale 8). Three of the present subscales which make up Factor 1 (Alienation, Social Nonconformity, and Discomfort) correlate highest with the corresponding MMPI scales mentioned above (Lanyon, 1973). The high loading of the Defensiveness scale may reflect the defensive attitude noted with substance abusers (Hoffman, 1970). Thus, the first factor may be a general measure of the maladaptive characteristics of substance abusers. The second factor is consistent with Johnson and Overall's (1973) introversionlextroversion factor as measured by the Expression scale. Although brief screening measures can be cost effective, the continued use of the Psychological Screening Inventory with samples of substance abusers as a measure of five personality factors is questionable. Even though factor scores could be developed for the current two-factor solution, the interpretation of the inventory would essentially be reduced to a decision of maladaptive versus not maladaptive behaviors. The loss of profile or configural interpretation sharply diminishes the potential usefulness. The present results seem consistent with the finding that the inventory did not reliably distinguish between hospitalized alcoholics and normal individuals (Jansen, 1972). Further research on the validity of the inventory with different patient populations (i.e., eating disorders, child abusers, etc.) should be conducted prior to using it with such groups. REFERENCES DILLON,W. R., & GOLDSTEIN, M. (1984) Multivariate analysis: methods and applications. New York: Wiey . GRAHAM,J. R., & STRENGER, V. E. (1988) MMPI characteristics of alcoholics: a review. Journal of Consulting and Clinical Psychology, 56, 197-205. HOFFMAN,H. (1970) Depression and defensiveness as self-descriptive moods of alcoholics. Psychological Reports, 26, 23-26. HOLLENBECK, G . P. (1972) A corn arison of analyses using the first and second generation Little Jiffy's. Educational ani~syrhologicalMeasurement, 32, 45-51. JANSEN, D. G. (1972) Use of the Psychological Screening Inventory with hospitalized alcoholics. Journal of Consulting and Clinical Psychology, 39, 170. JOHNSON, J. H., & OVERALL,J. E. (1973) A factor analysis of the Psychological Screening Inventory. Journal of Consulting and Clinical Psychology, 41, 57-60. LANYON, R. I. (1973) Psychological Screening Inventory: manual. Goshen, NY: Research Psychologists Press.
282
G. E. DUNN, ETAL.
LANYON,R. I. (1978) Factor structure of the Psychological Screening Inventory scales. Psychological Reports, 42, 383-386.
LANYON, R. I., JOHNSON, J. H., & OVERALL, J. E. (1974) Factor structure of the Psychological Screening Inventory in a normal population. Journal of Consulting and Clinical Psychology, 42, 219-223. OVERALL, J. E., JOHNSON, J. H., & LANYON, R. I. (1974) Factor structure and scoring of the PSI: an application of marker variable analysis. Multiwrlate Behavioral Research, 9, 407-422.
Accepted August 12, 1991
O Psychological Reports 1991
PRINCIPAL COMPONENTS ANALYSIS O F T H E PSYCHOLOGICAL SCREENING INVENTORY IN A SAMPLE O F SUBSTANCE ABUSERS ' GARY E. DUNN, ANTHONY M. PAOLO, JOSEPH J. RYAN
Dwight D. Eisenhower Department of Veterans Affairs Medical Center, LPavenworth, Kansar Summary.-A principal components analysis of responses to the Psychological Screening Inventory from a sample of substance abusers was conducted. Subjects were 153 inpatients admitted to a midwestern program for chemical dependency treatment. Means for age and education were 28.0 yr. (SD = 8.1) and 11.4 (SD= 1.81, respectively. Analysis indicated that a two-factor solution best described these data. Factor 1 reflected over-all maladiustment. while Factor 2 was a measure of extroversion. Clinical utility of the inventory was discussed.
Patients in alcohol and substance abuse programs should be evaluated for the presence of significant psychopathology. Since it is not always feasible to use lengthy psychological measures, brief personality screening instruments may offer cost effective methods of obtaining useful clinical information. Prior to using such measures, however, their validity should be established. Unfortunately, clinical use of the screening devices often tends to precede such evaluations. The Psychological Screening Inventory (Lanyon, 1973), which is frequently used with substance abusers, is a brief instrument designed to identify persons who are in need of more intensive psychological evaluation. The inventory consists of 130 true-false items which yield five scales: Alienation (Al), Social Nonconformity (Sn), Discomfort (Di), Expression (Ex), and Defensiveness (De). The validity of these dimensions was assessed by Lanyon and associates using a sample of 800 normal persons of 16 to 60 years of age. A series of item factor analyses generally supported the five subscales (Lanyon, Johnson, & Overall, 1974; Lanyon, 1978; Overall, Johnson, & Lanyon, 1974). Conversely, when Johnson and Overall (1973) investigated the factor structure of the items using a sample of 150 undergraduate psychology students, they found that three relatively uncorrelated factors best described the data (Introversion, Social Maladjustment, and Emotional Maladjustment). They concluded that, although a general correspondence between the three-factor solution and certain dimensions was apparent, it was not possible to define a five-factor solution that directly related to the five subscales.
'Requests for reprints should be addressed to Gary Durn, Ph.D., Psychology Service (IlbB), Dwight D. Eisenhower VAMC, Leavenworth, KS 66048.
280
G. E. D U N N , ETAL.
Although item factor analyses are of some psychometric interest, the clinical utility of most instruments rests on interpretation of the various scales, either individually or in concert. Factor solutions of these subscales may provide useful clinical interpretive hypotheses. Further, a principal components analysis has not been conducted with substance abusers, so this study is an initial attempt to respond to these issues. Subjects Subjects were 153 inpatients admitted to a midwestern chemical dependency treatment program. Means for age and education were 28.0 yr. (SD = 8.1) and 11.4 (SD = 1.8), respectively. Average T scores for the subscales were 56.4 (SD = 11.7) for Alienation, 60.7 (SD = 9.8) for Social Nonconformity, 53.2 (SD = 12.0) for Discomfort, 48.3 (SD = 8.2) for Expression, and 48.0 (SD = 10.0) for Defensiveness. There were 123 men and 30 women. Of the total sample, 71% were Caucasian, 25% were African-American, and the remaining 4% were Hispanic or Native American. Procedure As part of the standard intake assessment, all persons admitted into the treatment program during a six-month period completed the inventory. Principal components analysis (i.e., unity in the diagonal) followed by varimax rotation for the correlation matrix of the subscales was conducted to select the linear combinations that account for most of the total variance (Dillon & Goldstein, 1984). The number of factors to be retained was determined by Kaiser's eigenvalue > one (Hollenbeck, 1972). AU analyses were conducted using SPSS/PC + Version 3. RESULTSAND DISCUSSION Table 1 provides the factor solution for the subscales. As can be seen, the first factor consists of Discomfort, Social Nonconformity, Defensiveness, and ALienation scales and accounts for 43.9% of the variance. The second factor is made up of the Expression scale and accounts for 22.3% of the variance. The first factor appears to reflect over-all maladjustment and the second factor reflects extroversion. Although the results do not support the five scales developed by Lanyon (1978), they are generally consistent with the results reported by Johnson and Overall (1973). The current two-factor solution is U e l y a function of the population used. Graham and Strenger (1988), in a review of the characteristics of alcoholics, found significant elevations on MMPI scales that measure depression
'Data were collected while the first author was at Parallax Program Incorporated, Wichita,
Kansas.
FACTOR ANALYSIS O F THE PSI TABLE 1 OF THE SUBSCALES FACTOR STRUCTURE Scale
Factor I
Factor I1
Discomfort Social Nonconformity Defensiveness Alienation Ex~ression
.82 .81 -.68 .65 .03
-.29 .21 -.I1 -.37 .92
(Scale 2), anxiety (Scale 7), antisocial traits (Scales 4 and 9), and disordered thinking (Scale 8). Three of the present subscales which make up Factor 1 (Alienation, Social Nonconformity, and Discomfort) correlate highest with the corresponding MMPI scales mentioned above (Lanyon, 1973). The high loading of the Defensiveness scale may reflect the defensive attitude noted with substance abusers (Hoffman, 1970). Thus, the first factor may be a general measure of the maladaptive characteristics of substance abusers. The second factor is consistent with Johnson and Overall's (1973) introversionlextroversion factor as measured by the Expression scale. Although brief screening measures can be cost effective, the continued use of the Psychological Screening Inventory with samples of substance abusers as a measure of five personality factors is questionable. Even though factor scores could be developed for the current two-factor solution, the interpretation of the inventory would essentially be reduced to a decision of maladaptive versus not maladaptive behaviors. The loss of profile or configural interpretation sharply diminishes the potential usefulness. The present results seem consistent with the finding that the inventory did not reliably distinguish between hospitalized alcoholics and normal individuals (Jansen, 1972). Further research on the validity of the inventory with different patient populations (i.e., eating disorders, child abusers, etc.) should be conducted prior to using it with such groups. REFERENCES DILLON,W. R., & GOLDSTEIN, M. (1984) Multivariate analysis: methods and applications. New York: Wiey . GRAHAM,J. R., & STRENGER, V. E. (1988) MMPI characteristics of alcoholics: a review. Journal of Consulting and Clinical Psychology, 56, 197-205. HOFFMAN,H. (1970) Depression and defensiveness as self-descriptive moods of alcoholics. Psychological Reports, 26, 23-26. HOLLENBECK, G . P. (1972) A corn arison of analyses using the first and second generation Little Jiffy's. Educational ani~syrhologicalMeasurement, 32, 45-51. JANSEN, D. G. (1972) Use of the Psychological Screening Inventory with hospitalized alcoholics. Journal of Consulting and Clinical Psychology, 39, 170. JOHNSON, J. H., & OVERALL,J. E. (1973) A factor analysis of the Psychological Screening Inventory. Journal of Consulting and Clinical Psychology, 41, 57-60. LANYON, R. I. (1973) Psychological Screening Inventory: manual. Goshen, NY: Research Psychologists Press.
282
G. E. DUNN, ETAL.
LANYON,R. I. (1978) Factor structure of the Psychological Screening Inventory scales. Psychological Reports, 42, 383-386.
LANYON, R. I., JOHNSON, J. H., & OVERALL, J. E. (1974) Factor structure of the Psychological Screening Inventory in a normal population. Journal of Consulting and Clinical Psychology, 42, 219-223. OVERALL, J. E., JOHNSON, J. H., & LANYON, R. I. (1974) Factor structure and scoring of the PSI: an application of marker variable analysis. Multiwrlate Behavioral Research, 9, 407-422.
Accepted August 12, 1991
