Person. indicid.0(/f Vol. 22. No. 3, pp. 411416,
Pergamon
1997
Copyright c 1997 Elsevier Science Ltd
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Printed in Great Britain. All rights reserved zyxwvutsrqp
0191-8869/97 $17.00+0.00
SO191-8869(%)00205-X
GENDER
AND SCHIZOTYPAL
Robert
PERSONALITY
M. Roth and Jacinthe
FEATURES
Baribeau*
Laboratory
of Human Neuropsychology
and Neurophysiology
(LAHNN),
Department
of Psychology
(DS-413). Concordia University, 7141 Sherbrooke Ouest, Montreal, Quebec, Canada H4B lR6
(Received 20 December 1995; receivedfor publicarion I October 1996)
Summary-Schizotypal
personality is argued to be part of a spectrum of schizophrenia-related
disorders.
While salient gender differences in the symptomatology
of schizophrenics
have been reported, data with
regards to such differences in DSM-III defined schizotypal features are more limited. Right-handed
male
(N = 120) and female (N = 137) university students completed the Schizotypal Personality Questionnaire
(SPQ), a self-report instrument
designed to tap all nine features of DSM-III-R
schizotypal
personality
disorder. Results revealed that males are significantly higher only on the Eccentric/Odd
Behavior subscale,
while females score higher on the Ideas of Reference, Odd Beliefs/Magical
Thinking and Social Anxiety
subscales, as well as the Cognitive-Perceptual
Dysfunction
and Interpersonal
Deficits factors. Effect sizes
tended to be small, with only the Social Anxiety subscale yielding a moderate effect. 0 1997 Elsevier
Science Ltd. All rights reserved.
INTRODUCTION
A growing body of literature indicates significant gender differences among schizophrenic
patients
in terms of a variety of biological variables, course, outcome, symptomatology
and risk factors
(Bardenstein
& McGlashan,
1990; Flor-Henry,
1990; Goldstein,
Santangelo,
Simpson & Tsuang,
1990; Lewis, 1992; Raine, Harrison, Reynolds, Sheard, Cooper & Medley, 1990). In contrast to the
extensive work with schizophrenics,
limited research has been carried out on gender differences in
schizotypal personality,
as defined by Diagnostic and Statistical Manual of Mental Disorders (rev.
3rd edn; DSM-III-R;
American Psychiatric Association,
1987) criteria. This information
may be of
salience given that schizotypal personality appears to be part of a spectrum of schizophrenia-related
disorders with a common etiological basis (Torgersen,
1994).
Research using diagnostic interviews has provided only limited evidence for gender differences in
schizotypal personality
disorder (SPD). Although some studies have reported a higher prevalence
of SPD among male than female samples (Dahl, 1986; Gilbertson,
McGraw & Brown, 1986; Maier,
Lichterman,
Klinger, Huen & Hallmayer,
1992; Zimmerman
& Coryell, 1989), others have failed
to replicate this finding (Golomb, Fava, Abraham & Rosenbaum,
1995; Reich, 1987). In addition,
little information
is provided on potential gender differences in the individual features of SPD, as
evaluated using structured interviews. This may be of some importance as individual differences in
positive and negative schizotypal features have been reported to have different strengths of association with schizophrenia
(Torgersen, 1994) and both structural and functional frontal lobe integrity
(Raine, Sheard, Reynolds & Lencz, 1992).
Gender differences in the individual
features of schizotypal personality
have been investigated
primarily by means of self-report questionnaires
usually completed by students. The usefulness of
studying non-clinical
samples of schizotypals has been repeatedly demonstrated
(Lezenweger, 1993).
Many studies have reported gender differences on individual measures of schizotypal features. Men
tend to score higher on ‘negative’ symptom measures such as the Physical and Social Anhedonia
scales (Chapman,
Chapman
& Raulin, 1976; Muntaner,
Garcia-Sevilla,
Fernandez
& Torrubia,
1988), and women score higher on the more ‘positive’ symptom scales such as Perceptual Aberration,
Magical Ideation and Schizotypy (Chapman,
Chapman
& Raulin, 1978; Muntaner
et al., 1988;
Venables & Bailes, 1994). Men have also been found to score higher than women on scales reflecting
an asocial aspect of schizotypal personality, such as the Eysenck Psychoticism Scale and Hypomanic
Personality Scale (Bentall, Claridge & Slade, 1989; Eysenck & Eysenck, 1976). None of these scales,
*To whom all correspondence
should
be addressed.
411
412
Robert M. Roth and Jacinthe Baribeau
however, was specifically designed to tap all the salient phenomenological
characteristics
of SPD as
DSM-III or DSM-III-R
criteria. In particular, the psychosis-proneness
and Eysenck Psychoticism
scales appear to have limited convergent
validity with questionnaires
and structured
interview
designed to reflect SPD as defined by the DSM (Raine, 1987, 199 1).
Gender differences have also been observed in studies in which a number of individual schizotypal
and psychosis-proneness
scales are factor-analyzed
together. Such studies allow for the simultaneous
evaluation
of gender differences on multiple features of schizotypy, as well as the three to four
separate factors of schizotypal personality
that have emerged. Results of such investigations
have
generally confirmed reports based on individual scales, women scoring higher on positive symptom
factors and men higher on negative symptom factors (Bentall, et al., 1989; Claridge, McCreery,
Mason, Bentall, Boyle, Slade & Popplewell, 1996).
The Schizotypal Personality Scale (STA), unlike the above measures, is based on DSM-III criteria
(Claridge & Broks, 1984). Women tend to score higher than men on this scale. Recent factor analytic
studies have reported that the STA loads highly on both positive and social anxiety/cognitive
disorganization
symptom factors of schizotypal personality
(Bentall, et al., 1989; Claridge et al.,
1996). To our knowledge, separate factors and/or individual features of SPD have not been reported
to have corresponding
factors and subscales within the STA. Thus, although the STA appears to
be somewhat biased towards positive schizotypal features, further investigation
is required in order
to determine to what degree gender differences on the scale are differentially
influenced by clusters
of items related to positive and social anxiety/cognitive
disorganization
factors and features of
schizotypal personality.
Raine (1992) has recently provided more evidence for gender differences in DSM-III-R
schizotypal
personality features using the Schizotypal Personality Questionnaire
(SPQ; Raine, 1991). The SPQ
is a 74-item self-report questionnaire
designed to assess all nine schizotypal features as defined in
DSM-III-R.
Adequate reliability and validity has been demonstrated
(Raine, 1991). Three factors
make up the SPQ: cognitive-perceptual
dysfunction,
interpersonal
deficits and disorganization.
This
factor structure has been replicated and shown to hold for both males and females (Raine, Reynolds,
Lencz, Scerbo, Triphon & Kim, 1994). Consistent
with studies using incomplete
assessments of
schizotypal
personality,
results revealed that female college students score higher on the more
positive symptom subscales of ides of reference and odd beliefs/magical
thinking, as well as the
cognitive-perceptual
factor score. In contrast males score higher on the negative symptom subscales
of no close friends and constricted affect, but no gender difference was observed on the interpersonal
deficits factor score. These findings appear robust as they were replicated in a second sample. A
more recent investigation
also using the SPQ failed to detect higher scores for females on the positive
features, but did find that men obtained higher scores on a number of the negative symptom
subscales (Miller & Burns, 1995).
The present study attempts to provide further evidence for gender differences in schizotypal
personality features using a non-clinical
sample. Since previous work has demonstrated
a significant
relationship
between handedness and scores on the SPQ (Kim, Raine, Triphon & Green, 1992) and
handedness
was not controlled
for in previous investigations
using the SPQ, only right-handed
individuals were assessed.
METHOD
Subjects
A total of 264 right-handed
undergraduate
university students volunteered to complete the SPQ.
In order to maximize diversity within our sample, and reduce the potential bias that may be
introduced
by the common method of sampling of subjects from introductory
psychology courses
(Lezenweger & Korfine, 1992) the SPQ was distributed
in undergraduate
classes covering a wide
variety of study areas, as well as in areas of the university in which heterogeneity
of the population
with regards to major is likely to be maximized (e.g. cafeteria). Handedness was determined by selfreport. The sample consisted of 137 women and 120 men between the ages of 18 and 26. The mean
age of the men was 21.90 (SD = 1.95) years and 21.07 (SD = 1.92) years for the women.
Gender and schizotypal personality features
Table
I. Means.
standard
deviations.
f-tests and effect sizes (d,l comparing
factor
men (N = 121) and wanen
scores and total score of the SPQ
Me ”
Measure
Cognitive-perceptual
perceptual
Suspicious/paranoid
Interpersonal
Contricted
Women
6.54
I I .99
5.89
-2.88
0.004’
0.36
2.52
3.98
2.41
-2.56
0.01 I’*
0.35
thinking
2.01
2.03
2.75
I .99
-2.98
0.003**
0.37
experiences
2.39
2.06
2.70
2.07
-
I.19
0.234
0.15
2.17
I.91
2.51
I .82
-
1.72
0.087
0.22
9.43
6.40
10.93
5.14
-2.06
2.12
I .83
I .99
I .60
Factor
SD
f
No close friends
2.40
2.30
2.36
1.70
Social
2.74
2.12
4.02
2.20
5.57
3.90
anxiety
Disorganization
Odd
Total
factor
6.1 I
3.41
2.56
3.56
2.47
behavior
2.69
2.28
2.0 I
2.1
23.14
12.73
speech
Eccentrtc/odd
SPQ sccwe
Note:
**P
Significance
< 0.0125,
rl
3.19
affect
M
P
9.15
ideation
deficits
three
SD
factor
beliefs/magical
Unusual
(N = 138) on the nine subscales,
zyxwvutsrqponmlkjihgfedcbaZYXWVUTS
M
Ideas of reference
Odd
413
levels
within
for
the total
the interpersonal
SPQ
score
deficits
4.17
and
three
factor
***P
factors
< 0.016,
*P < 0.05,
and within
0.16
I .08
for
-
subscales
the disorganization
0.26
0.08
0.02
0.001***
0.59
0.283
0.13
0.644
0.06
2.5 I
0.013****
0.3 I
1.93
0.054
0.25
-0.44
I
0.041’
0.542
0.870
-4.66
10.03
25.92
are
0.61
within
factor
the cognitive-perceptual
****P
factor
< 0.025.
Measure
As indicated previously, the SPQ (Raine, 1991) is designed to assess all nine features of SPD. A
three-factor solution has been found to be most appropriate for the SPQ, the factors being cognitiveperceptual dysfunction,
interpersonal
deficits and disorganization
(Raine et zyxwvutsrqponmlkjihgfedcbaZY
al., 1994). The subscales
that compose the cognitive-perceptual
dysfunction
factor are ideas of reference, odd beliefs/magical
thinking, suspiciousness/paranoid
ideation and unusual perceptual experiences. No close friends,
constricted affect and social anxiety make up the interpersonal
deficits factor. The disorganization
factor is composed of the odd speech and eccentric/odd
behavior subscales. Consistent with Raine
(1992), factor scores were obtained by summing the scores of the individual subscales composing
each factor. The SPQ has been found to have good psychometric
properties (Raine, 1991; Raine et
al., 1994). In particular,
Raine (1991) has found that 55% of subjects scoring in the top 10% on the
SPQ fulfil DSM-III-R
criteria for SPD according to the Structured Clinical Interview for DSM-IIIR Personality Disorders (Spitzer, Williams & Gibbon, 1987).
RESULTS
In order to permit a direct comparison
of our results with those of Raine (1992), two-tailed ttests were performed on the nine subscale scores, three factors, and the total SPQ score. Effect sizes
(d) were also calculated (Cohen, 1988). Since multiple r-tests are likely to inflate the probability
of
Type I error, significance level was set at P < 0.05 for comparisons
involving the three factor and
total SPQ scores. Bonferroni-adjusted
alpha levels were used to evaluate the significance of individual
schizotypal features within each factor. Alpha levels were 0.0125 (0.05/4) for the cognitive-perceptual
factor, 0.016 (0.05/3) for the interpersonal
deficits factor, and 0.025 (0.05/2) for the disorganization
factor. Descriptive statistics, results of the t-tests and effect sizes are presented in Table 1.
Women were found to score significantly higher than men on the ideas of reference (P = 0.01 l),
odd beliefs/magical
thinking (P = 0.003) and social anxiety (P = 0.001) subscales, as well as the
cognitive-perceptual
dysfunction
(P = 0.004) and interpersonal
deficits (P = 0.041) factors. A trend
was also found indicating that women score higher than men on the total SPQ score (P = 0.054).
Men scored significantly
higher than women only on the eccentric/odd
behavior
subscale
(P = 0.013). Effect sizes for the majority
of these differences tended to be slightly above the 0.2
criteria for a small effect propounded
by Cohen (1992). Only the effect size of 0.59 obtained for
social anxiety could be considered a moderate effect (i.e. 0.5 to 0.8).
DISCUSSION
The present results are generally consistent with those reported
women score higher than men on the more positive schizotypal
by Raine (1992). We found that
characteristics,
namely ideas of
414
Robert M. Roth and Jacinthe Bar&au
reference and odd ~liefs/magical thinking, as well as the cognitive-perceptual factor, The robustness
of these findings is clear as they appear both in our study and Raine’s. With regards to the trend
previously observed for males to score higher on eccentric/odd behavior, our results indicate a
significantly greater score for males. As in previous investigations using the SPQ, no significant
gender differences emerged for the unusual perceptual experiences and odd speech features. Thus
our findings for the positive schizotypal features are consistent with those obtained by Raine, though
discrepant with regards to Miller and Burns (1995). The latter study did not find gender differences
on the cognitive-perceptual factor score or any of its features.
Results for the negative features are inconsistent across investigations. In our sample women
scored significantly higher than men on the interpersonal deficits factor. The opposite result was
obtained by Miller and Burns. In addition, while both Raine and Miller and Burns found that males
scored significantly higher on the negative features of no close friends and constricted affect, we did
not find such differences and extremely small effect sizes. It is interesting to note that while there
are important differences between our study and the others in terms of negative features, all three
investigations report significantly greater social anxiety in females than males. A higher level of
social anxiety in females is consistent with studies indicating greater manifestation of affective
symptoms in female than male schizophrenics (Bardenstein & McGlashen, 1990).
A trend was observed indicating that women, as a group, scored somewhat higher than men on
the total SPQ score. We could not compare this finding to previous results on the SPQ as the other
investigations did not provide this comparison. Another way of looking at the implications of this
finding, however, is to determine how many of our subjects actually fulfil diagnostic criteria for
SPD. Although we did not conduct diagnostic evaluations with our subjects, Raine (1991) found
that 55% of subjects scoring above his 10% high-point cut-off total SPQ score of 41 ful~lled
diagnostic criteria for SPD. In the present sample 5.4% of females and 10% of males obtained
scores above this cut-off. It is therefore probable that in our sample almost twice as many males
than females would fulfil diagnostic criteria for SPD. That as a group females had a higher mean
total SPQ score, but individually are less likely than men to fulfil SPD diagnostic criteria, is
consistent with studies reporting a higher prevalence of SPD among males (Dahl, 1986; Gilbertson
et zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
al., 1986; Maier et al., 1992; Zimmerman & Coryell, 1989).
The present results offer strong support for the higher level of positive features observed in
females in previous studies of schizotypal personality (Claridge & Hewitt, 1987; Raine, 1992),
psychosis-proneness (Muntaner et al., 1988) and schizophrenia (Bardenstein & McGlashen, 1990;
Castle & Murray, 1991). In contrast to the positive features, results for the negative schizotypai
features fail to support previous investigations of student samples. Disagreement with regards to
gender differences in negative features also characterises the schizophrenia literature, with some
studies reporting more negative symptoms in males (Goldstein ei al., 1990; Haas, Sweeney, Keilp
& Hein, 1989) and others finding no differences (Josiassen, Roemer, Johnson & Shagass, 1990).
The reason(s) underlying the inconsistencies between our investigation and those of other groups
using the SPQ (Miller & Burns, 1995; Raine, 1992) are unclear. All three studies employed undergraduate university students of comparable age. The cultures in which samples were obtained are
also quite similar (U.S.A. and Canada). The SPQ and other schizotypy questionnaires have generally
been designed with items sensitive to gender bias and social desirability removed during test
construction (Chapman, Chapman & Kwapill, 1995; Raine, 1991). Gender differences in schizophrenic symptomatology do not appear to be largely accounted for by sex role expectations and
social skills (Andia & Zisook, 1991). Nevertheless, the possible effects of other sociocultural factors
on schizotypal symptomatology and responding to schizotypy questionnaires is deserving of more
attention. In addition, while our sample is somewhat more limited in size, effect sizes are comparable
to those reported by Raine (1992). Statistical control for multiple comparisons is more stringent in
the present study and that of Miller and Burns than Raine’s investigation, However, even when an
alpha level of 0.005 (used by Miller and Burns) is applied to the Raine’s results, little change in his
interpretations are warranted. It is also unlikely that our use of only right-handed subjects can
account for most of the differences between studies. Handedness had been previously found to be
significantly related to the cognitive-perceptual factor and the odd speech subscale of the SPQ (Kim
et al., 1992). None of the investigations using the SPQ has reported gender differences in odd speech,
and only Miller and Burns failed to observe a significant effect on the cognitive-perceptual factor.
Gender and schizotypai personality features
415
The question of whether handedness
has a differential
influence for males and females on the
cognitive-perceptual
factor awaits investigation.
Further exploration
of variables that may interact
with gender in producing differences in schizotypal features is clearly required.
The use of factor scores to group Ss for investigation is common in studies of schizophrenia and
SPD. Such composite scores may mask potentially salient individual differences in the relationship
between specific schizotypal features and other variables. As demonstrated in this and other studies,
group differences on factor scores are unlikely to be reflected in all the individual features that make
up a given factor. Using appropriate control over Type I error, studies of subgroups based on factor
scores should therefore consider the independent contribution of subscales within each factor on
the dependent measures under investigation.
Consideration of the factors and features of schizotypal personality may also help understand
gender differences in the performance of high schizotypes on experimental paradigms. It has been
frequently observed that the relationship between schizotypy and a few experimental measures is
stronger and more consistent for males than females (Claridge, Clark & Beech, 1992; Gruzelier,
1994). One such finding indicates that the relationship between schizotypy and performance on tests
with different sensitivities to left and right hemisphere disturbance is significantly moderated by
gender (Claridge et al., 1992; Gruzelier, 1994). Of particular pertinence, Gruzelier (1994) observed
that this gender effect on variables related to hemispheric asymmetry was itself moderated by the
type of schizotypal syndrome (corresponding to the positive, negative and disorganization factors,
discussed in the current paper) prominent among Ss of each gender. A complex interaction between
gender, syndrome and ex~rimental task has also been reported in studies of schizophrenic patients
(Gruzelier, 1994). Such an interaction may at least partially account for the differential risk of males
and females for the development and expression of negative and positive syndromes and particular
symptoms of schizotypal personality and schizophrenia, as well as inconsistent findings on potential
markers for schizophrenia.
REFERENCES
American Psychiatric Association. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA
(1987). Diagnostic and statistical manual of‘mental disorders (Ref. 3rd edn). Washington,
DC: American Psychiatric Press.
Andia, A. M. & Zisook, S. (1991). Gender differences in schizophrenia: A literature review, Annals ofclinical Psvchiuiry. 3,
333-340.
Bardenstein, K. K. & McGlashan, T. H. (1990). Gender differences in affective, schizoaf%ctive and ~hizophrenic disorders:
A review. Sch~zophrenja Research. 3, 159- l 72.
Bentall, R. P., Claridge. G. S. & Slade, P. D. (1989). The multidimensional nature of schizotypal traits: A factor analytic
study with normal subjects. British Journal zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFED
of Clinical Psy chology , 28.363- 375.
Castle, D. J. & Murray, R. M. (1991). The neurodevelopmental basis of sex differences in schizophrenia. Psy chological
M edicine, 21, 565- 575.
Chapman, J. P., Chapman, L. J. & Kwapill, T. R. (1995). Scales for the measurement of schizotypy. In A. Raine, T. Lencz
& S. A. Mednicj (Eds), SchizoIy palpersonaliry (pp. 79-106). New York: Cambridge.
Chapman, L. J., Chapman J. P. & Raulin, M. L. (1976). Scales for physical and social anhedonia. Journal o/‘Abnormal
Psy chology , 85, 374- 382.
Chapman, L. J., Chapman, J. P. & Raulin M. L. (1978). Body-image aberration in schizophrenia.
Journal qf Abnormal
Psy chology , 87, 399- 407.
Claridge, G. (1994). Single indicators of risk for schizophrenia: Probable fact or likely myth? Schizophrenia Bulletin, 20, I51168.
Claridge, G. & Broks, P. (1984). Schizotypy and hemisphere function. I. Theoretical considerations and the measurement of
schizotypy. Personu~jty and ~ndividuaf DiSferences, 5,633# 8.
Claridge, G. S., Clark, K. H. & Beech, A. R. (1992). Lateralization of the ‘negative priming’ effect: Relationship with
schizotypy and with gender. British Journal of Psy cholog~f, 83, 13- 23.
Claridge, G. & Hewitt, J. K. (1987). A biometric study of schizotypy in a normal population. Persona/& und ~ndizliduu~
Dijjkrences. 8, 303- 3 12.
Claridge,G., McCreery, C., Mason, O., Bentall, R., Boyle, G., Stade, P. & Popplewell, D.
(1996). The factor structure of
‘schizotypal’ traits: A large replication study. British Journal @ ‘Clinical Psy chology . 35. IO3-115.
Cohen, J. (1988). Statisficalpower analy sis for the behavioral sciences. Hillsdale, NJ: Erlbaum.
Cohen, J. (1992). A power primer. Psy chological Bulletin, 112. 155- I59.
Dahl, A. A. (1986). Some aspects of the DSM-III personahty disorders illustrated by a consecutive sample of hospitalized
patients. Arra Psy chiawica Scandinavica, 228 (Suppl.), 61-67.
Eysenck, H.J. & Eysenck, S. B. G. (1976). Psy rhoricism as a dimension qj’personalitJ_ London: Hodder 8~ Stoughton.
Flor-Henry. P. (1990). Influence of gender as related to other psychopathological syndromes. Schizophrenia Bullefin, 16,
21 I-227.
Gilbertson, A. D., McGraw, L. K. & Brown, N. E. (1986). A different empirical perspective on sex bias in the diagnosis of
DSM-111 axis II disorders. Psychiatry Quarter/y, 58, 144147.
416
Robert
M. Roth
and
Jacinthe
Baribeau
Goldstein, J. M., Santangelo,
S. L., Simpson, J. C. & Tsuang, M. T. (1990). The role of gender in identifying subtypes of
schizophrenia:
A latent class analytic approach. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFE
Schjzophrenja BalIeiin, i&263- 275.
Golomb, M., Fava, M., Abraham,
M. & Rosenbaum,
J. F. (1995). Gender differences in personality
disorders. Americun
Journal qf Psychiatry, 132, 579- 582.
Gruzelier, J. H. (1994). Syndromes of schizophrenia
and schizotypy, hemispheric imbalance and sex differences: Implications
for developmental
psychopathology.
Internaiional Journal of Psy chophy siology , 18, 167- 178.
Haas, G. L., Sweeney, J. A., Keilp. J. & Hein, D. A. (1989). Sex dsferences in neurocognition, Presented at the Annual
Meeting of the American Psychological
Association,
San Francisco, CA, May.
Josiassen, R. C.. Roemer, R. A., Johnson, M. M. & Shagass, C. (1990). Are gender differences in schizophrenia
reflected in
brain event-related
potentials. Schkophrenia Bulletin, 16, 229- 246.
Kim, D., Raine, A., Triphon, N. & Green, M F. (1992). Mixed handedness and features of schizotypal personality in a
nonclinical sample. Journal of Nervous and M ental Disease. 180, 131- I 33.
Lewis, S. (1992). Sex and schizophrenia:
Vive la difference. British Journal ofpsyehiutry, 161.445- 450.
Lezenweger, M. F. (1993). Explorations
in schizotypy and the psychometric
high-risk paradigm.
In L. J. Chapman, J. P.
Chapman & D. Dowles (Eds), Progress in e.~perjmentai personality and ps~~~hoputholog~research {Vol. 16, pp. 66-l 16).
New York: Springer.
Lezenweger, M. F. & Korfine, L. (1992). Confirming the latent structure and base rate of schizotypy: A taxometric analysis,
Journal of Abnormal Psy cholog.&>,IOf, 567- 57 1.
Maier, W., Lichterman,
D., Klinger, T., Huen, R. & Hallmayer. J. (1992). Prevalence of personality disorders (DSM-III-R)
in the community.
Journal of Personal& Disorders, 6, 187- 196.
Miller, L. S. & Burns, S. A. (199.5). Gender differences in schizotypic features in a large sample of young adults. Journal qf
Nervous and M ental Disease, 183, 657- 661.
Muntaner,
C., Garcia-Sevilla,
L., Fernandez, A. & Torrubia, R. (1988). Personality dimensions, schizotypal and borderline
personality
traits and psychosis proneness. Personality and Individual Differences, 9, 257- 268.
Raine, A. (1987). Validation of schizoid personality
scales using indices of schizotypal and borderline personality disorder
in a criminal population.
British Journal of Clinical Psy chology , 26, 305- 309.
Raine, A. (1991). The SPQ: A scale for the assessment of schizotypal personality based on DSM-III-R criteria. Schizophrenia
Bulletin, I?‘, 555- 564.
Raine,
A. (1992). Sex differences
in schizotypal
personality
in a nonclinical
population.
Journal of Abnormal Psy chology ,
IOI, 361- 364.
Raine. A., Harrison,
G., Reynolds,
G. P.. Sheard, C., Cooper, J. E. & Medley, J. (1990). Structural
and functional
characteristics
of the corpus callosum in schizophrenics,
psychiatric
controls,
and normal controls:
An MRI and
neuropsychological
examination.
Archives qf General Psychiatry, 47, 1060- 1964.
Raine, A., Reynolds, C., Lencz, T., Scerbo, A., Triphon, N. & Kim, D. (1994). Cognitive-perceptual.
interpersonal,
and
disorganized
features of schizotypal personality.
Schizophrenia Bu/letin, 20, 191-201.
Raine. A.. Sheard, C., Reynolds, G. P.. Lencz, T. (1992). Pre-frontal
structural
and functional
deficits associated with
individual differences in schizotypal personality.
Schizophrenia Research, 7, 237- 247.
Reich, J. (1987). Sex distribution of DSM-III personality disorders in psychiatric outpatients.
American JournalqfPsychiatry,
144,485- 488.
Spitzer,
R. L., Williams, J. B. W. & Gibbon, M. (1987). Structured clinical interrie\c,for DSM -III-R personality disorders:
New York: New York State Psychiatric
Institute.
Torgersen, S. (1994). Personality deviations within the schizophrenia
spectrum. Arta P.yhia/rica Scandinarica, 90 (Suppl.
384). 40-44.
Venables, P. H. & Bailes. K. (1994). The structure of schizotypy, its relation to subdiagnosis
of schizophrenia
and to sex and
age. British Journal qf Clinical Psy chology , 33. 277- 294.
Zimme~an.
M. & Coryell, W. (1989). DSM-III personality disorder diagnoses in a nonpatient sample. Archives sf Generai
SCID-II.
Ps~c~?iatr~,46,682X% 9.