Open Journal of Psychiatry, 2011, 1, 110-114 OJPsych
doi:10.4236/ojpsych.2011.13016 Published Online October 2011 (
Published Online October 2011 in SciRes. http://www.scirp. org/jour nal/OJP sych
Three-factor structure of self-report schizotypal traits in a
French nonclinical sample
Jérôme Brunelin1,2*, Patrick Dumas1, Mohamed Saoud1,2, Thierry d’Amato1,2, Emmanuel Poulet1,2
1CH Le Vinatier, Bron, France;
2Université de Lyon, Lyon, France; Université Ly on 1, Lyon, France; Bron, France.
Email: *
Received 6 June 2011; revised 10 July 2011; accepted 18 July 2011.
Evidence suggests that the structure of psychosis-
proneness in the general population may involve
three distinct related dimensions. Therefore we con-
ducted a study, using a wider range of measures, to
explore the factorial structure of schizotypy assessed
by a mixed self-report Schizotypal Traits Question-
naire (mSTQ) in young French healthy individuals.
Raine’s Schizotypal Personality Questionnaire [SPQ]
and four of the Chapman’s scales [Magical Ideation
Scale-MIS; Perceptual Aberration Scale-PAS; Re-
vised Physical Anhedonia Scale-PhA and Revised
Social Anhedonia Scale-SA] were combined to form a
mSTQ which was administered to 232 French un-
dergraduate students aged from 18 to 25 years old. A
Principal Component Analysis [PCA] was carried out
on scores for each scale to examine the factorial
structure of schizotypal traits in this sample. PCA
evidenced a three-factor model of schizotypy in the
sample as a whole and even in the lower score sub-
sample. The three factors were “positive or cognitive-
perceptual”, “negative or social-interpersonal” and
“disorganization” latent. Schizotypy, as assessed by
these scales, is a multidimensional construct com-
posed by at least three dimensions in this nonclinical
sample. This factorial structure is similar to those of
schizophrenia symptoms which raise the hypothesis
of a continuum from normality to schizophrenia via
schizotypal traits
Keywords: Schizotypy; Psychosis Proneness Scales;
Schizotypal Personality Questionnaire; Three-Factor Str-
ucture; Schizophrenia
Many researchers acknowledges the existence of a schiz-
ophrenia spectrum, from normality to psychosis, of which
schizophrenia is considered to be one extreme. Recogni-
tion of a schizophrenia spectrum received impetus from
the genetic “high-risk” approach of studying the rela-
tives of patients with schizophrenia [1,2]. Another strat-
egy consists in the study of psychotic-like traits in the
general population [3-5] through the development of
schizotypy and psychosis-proneness scales [6-8] stem-
med from the idea that traits which may predispose to
schizophrenia can be identified in non-clinical popula-
tions [9]. However, schizophrenia itself can no longer be
viewed as a unitary construct; rather there is a growing
consensus that the clinical symptoms seem to cluster into
at least three distinct syndromes [10-12]. In turn, schiz--
otypy in non clinical samples has been shown to have a
similar dimensional structure, with factors resembling at
least 3 dimensions of schizophrenia: positive, negative,
and cognitive-disorganisation [3,4,13]. However, some
authors have evoked the possible influence of sociocul-
tural context in sch izotypal construct [14].
The aim of the present study was to look at schizo-
typal symptoms factorial structure in a French non clini-
cal sample as measured by a mixed Schizotypal Traits
Questionnaire (mSTQ). Factor analyses were conducted
on a sample of undergraduate students. It was expected
that the factors usu ally identified in sch izophrenia and in
studies using the SPQ: Schizotypal Personnality Ques-
tionnaire in other population [4,15] would appear; name-
ly, a factor that predominantly reflects positive symp-
toms, a factor that predominantly reflects negative symp-
toms, and a disorganized factor, suggesting a continuum
from normal to psychosis.
2.1. Subjects
Non clinical undergraduate students (n = 232) of both
genders (Females = 125; Males = 107), from 18 to 25
years old (Age ± standard deviation: 21.17 ± 1.47), were
J. Brunelin et al. / Open Journal of Psychiatry 1 (2011) 110-114
Copyright © 2011 SciRes. OJPsych
recruited through campus public advertising which call-
ed for “a 50 euros paid study on character traits and per-
sonality”. Written informed consent was obtained from
all participants and the study was approved by the Ethi-
cal Committee of Lyon B. All participants were free of
serious somatic illness (including diabetes and neuro-
logical disorders), mood disorder, suicidal risk and of
DSM-IV axis I psychotic personal history as explored
through SADS examination [16]; none of them had ever
received antipsychotic or antidepressant medications.
Moreover, because of the genetic part of schizophrenia,
subjects with family history of schizophrenia were not
included in the study. Subjects with current or past his-
tory of substance abuse were not included in this study.
However, knowing relationship between cannabis and
schizotypal traits [17], cannabis consumers were in-
2.2. Psychometric Investigations
Among various instruments proposed to measure Schi-
zotypal traits in clinical and non clinical samples, we
have chosen five French-version [18-21] separate self-
report scales widely used in this field.
Four of the Psychosis Proneness Scales [PPS] de-
veloped by Chapman and colleagues to measure
traits known to be more frequent in subjects who
later developed psychotic disorders, i.e.: The Magi-
cal Ideation Scale [MIS] [18,19] measures the ac-
ceptance of causal relationships not widely held by
the dominant culture (e.g. “at times I perform cer-
tain little rituals to ward off negative influences”);
the Perceptual Aberration Scale [PAS] [18,19]
measures body image and object-related perceptual
distortions (e.g. “at times I have wondered if my
body was really my own”), the revised Physical
Anhedonia Scale [PhA] [20,21] measures a lack of
responsiveness to sensory experiences (e.g. “I have
had very little desire to try new kinds of food”) and
the Revised Social Anhedonia Scale [SA] [21] re-
flects the negative aspects of psychosis, and consists
of items assessing the lack of enjoyment from social
contact, physical activities, coupled with aversion to
emotional and physical intimacy (e.g., “Are you
much too independent to get involved with other
The Schizotypal Personality Questionnaire [SPQ]
[22,23] which contains 74 items evaluating the nine
SPD DSM-IV criteria leading to a total score and
nine possible sub-scores (Ideas of reference; Exces-
sive social anxiety; Odd beliefs or magical thinking;
Unusual perceptual experiences; Odd or eccentric
behavior; No close friends; Odd speech; Constricted
affect; Suspiciousness). These allow both categorical
and dimensional approaches of Schizotypal Person-
ality Disorder.
Participants have to check all the 240 items of the 5
scales. Items were presented in a in a combined order [24]
as a mixed Schizotypal Traits Questionnaire (mSTQ). To
limit the risk of contamination of questionnaire respon-
ses by drug effects, we instructed subjects not to report
drug-related experiences when they completed the ques-
2.3. Statistical Analysis
Pearson correlations were used to examine relationships
between scores on PPS and SPQ sub-scales. Then, scores
of the 232 participants on the SPQ sub-scales, PAS, MIS,
PhA and SA were subjected to Principal Component
Analysis (PCA). The number of extracted factors was
decided using Kaiser ’s criteria and the Cattell’s scree test
before subsequent VARIMAX rotation. Then, an explo ra-
tory factor analysis of the SPQ sub-scales, PAS, MIS,
PhA and SA was conducted with only the low scorers (n
= 183), identified as subjects who scored under the
cut-off score on one or more of the five psychometric
scales (Scale—lower cut-off score—n =; PAS—3/35—n
= 82; MIS—5/30—n = 87; PhA—9/61—n = 78; SA
—7/40—n = 80; and SPQ—7/74—n = 29; see [19,23]
for more information about cut-off score calculation).
PCA has been carried out on the correlation matrix for
scores at each PPS and each of the nine SPQ subscales.
PCA revealed three factors with an eigenvalue of 1 or
greater. The model accounted for 65.4% of the variance.
The first factor, which consisted of MIS, PAS, and
four SPQ subscales (“Suspiciousness”, “Odd or eccen-
tric behavior”, “Unusual perceptual experiences”, and
“Ideas of reference”) accounted for 39.1% of the total
variance. This factor is clearly consistent with a positive
syndrome factor.
The second component, which consisted of SA, PhA,
and three SPQ subscales evaluating “Excessive social
anxiety”, “No close friends” and “Constricted affect”,
accounted for 18.1% of the total variance. This factor is
predominantly a negative syndrome factor.
The third component accounted for 8.2% of the total
variance and consisted of the “Odd speech” SPQ sub-
scale scores. This factor is most consistent with disor-
An explorator y factor analysis of the SPQ, PAS, MIS,
PhA and SA was conducted on just the low scorers,
identified as any student who scored under the cut-off
score on any of the five scales (n = 183). The PCA again
revealed the same 3 factors with an eigenvalue of 1 or
greater (see Table 1).
J. Brunelin et al. / Open Journal of Psychiatry 1 (2011) 110-114
Copyright © 2011 SciRes. OJPsych
The present study aimed, to explore the factorial structure
of schizotypal traits in young French healthy individuals by
the mean of self-report scales. PCA yielded three factors
that paralleled highly with previously reported factors;
namely, negative or social-interpersonal factor (i.e. “Exces-
sive social anxiety”, “No close friends”, and “Constricted
affect”, and Physical and Social anhedonia), positive or
cognitive-perceptual (i. e. “Magical ideation”, “Perceptual
aberration”, “Unusual perceptual experiences”, “Ideas of
reference”, “Suspiciousness”, and “Odd or eccentric be-
havior ”) an d dis organi zati on (i.e. “Odd speech”). Strikingly,
factor analyses with only the nonclinical low scorers re-
vealed the same three-factors too, thus supporting the
Table 1. Percentage of total variance and factor solution for the
9 subscales of the schizotypal personality questionnaire (SPQ),
the perceptual aberration scale (PAS), the magical ideation
scale (MIS), the revised physical anhedonia scale (PhA), and
the revised social anhedonia scale (SA) using the total sample
(n = 232) and the low scorers (n = 183).
Total sample (n = 232) Low scorers (n = 183)
Factor 1 Factor 2 Factor 3 Factor 1 Factor 2Factor 3
Percentage of
total variance 39.1 18.1 8.2 33.2 17.48.8
1 Ideas of
Reference (SPQ) 0.821 –0.182 0.073 0.768 0.159 0.165
2 Excessive Social
Anxiety (SPQ) 0.486 0.320 0.359 0.354 0.3690.253
3 Odd Beliefs or
Magical thinking
(SPQ) 0.574 –0.541 0.313 0.572 –0.5 0.404
4 Unusual Percep-
tual Experiences
(SPQ) 0.788 0.348 0.098 0.788 0.243 0.062
5 Odd or Eccentric
Behavior (SPQ) 0.716 0.040 0.137 0.632 0.199 0.169
6 No Close Friends
(SPQ) 0.464 0.680 0.121 0.330 0.712 0.137
7 Odd Speech
(SPQ) 0.526 0.074 0.458 0.479 0.085 –0.478
8 Constricted
Affect (SPQ) 0.527 0.577 0.264 0.414 0.6630.226
9 Suspiciousness
(SPQ) 0.713 0.171 0.179 0.633 0.221 0.126
10 PAS 0.791 0.214 0.218 0.751 0.202 0.22
11 MIS 0.775 0.382 0.248 0.765 0.322 0.266
12 PhA 0.029 0.593 –0.509
0.218 0.459 0.523
13 SA 0.448 0.657 0.330 0.376 0.634 0.387
continuity view of psychosis and the multidimensional-
ity of psychosis-proneness (Figure 1). These findings
further replicate and support the three-factor model of
schizotypal personality, as measured by the SPQ and
PPS, in non clinical undergraduates students. These re-
sults also support previous findings suggesting that dif-
ferent proneness and schizotypal traits scales relate to
different underlying aspects of schizophrenia [7].
Some methodological issues should be considered that
may have influenced our results. First, subjects were no t
randomly selected leading to a possible concentration of
pathological individuals. However, this bias was limited
because subjects were clearly informed that no diagnosis
would be delivered; Moreover, the study was very at-
tractive for every students given they were paid for par-
ticipation. Second, schizotypy was evaluated only through
self-report scales leading to a possible misestimating of
some schizotypal traits like oddness, althoug h the use of
a combined scale diminishes this bias. Conversely,
Constr icted A ffe ct
No Close
Odd Speech
Excessive Social
Odd Belie f s /
Magical Thinking
Ideas of Refe rence
Odd / Eccentric
Figure 1. Path diagram illustrating the three factor structure of
self-report schizotypy in a nonclinical sample of 232 students
SPQ = schizotypal personality questionnaire; PPS = psychosis
proneness scales; PAS = perceptual aberration scale; MIS =
magical ideation scale; PhA = physical anhedonia scale; SA =
social anhedonia scale. Observed variables are represented by
squares, latent factors by circles. Single-headed arrows repre-
sent factor loadings.
J. Brunelin et al. / Open Journal of Psychiatry 1 (2011) 110-114
Copyright © 2011 SciRes. OJPsych
this method limits the rater’s subjectivity. On the other
hand, one can hypothesize that analysing of other pro-
neness scales would permit the discrimination of other
factors seen in schizophrenia like anxiety/depression or
impulsivity/excitation [12]. Finally, as previously re-
ported [17], our sample could be divided into three
groups according to cannabis use typology: those who
had never used cannabis (n = 126), those who were past
or occasional users (n = 65), and those who were regular
users (n = 41). Higher scores on the SPQ and the MIS
were characterized by regular and past or occasional
users compared with those who had never used cannab is.
The fact that lower scorers were also non cannabis users
is in accordance with recent report that the onset of
schizotypal symptoms generally precedes the onset of
cannabis use [25] .
These remarks being taken into account, the results of
the present study are consistent with prior research. In-
deed, researchers have devised many questionnaires and
structured interviews to measure schizotypal traits and,
when various combinations of these measures have been
subjected to factor analytic procedures, with either nor-
mal or clinical samples, three factors generally emerge
[4,9,13,15,26-28]. Moreover, this three-factor model of
schizotypal personality seems invariant across age and
gender [29]. An alternative, four-factor model was sug-
gested by the results of several large-scale factor-ana-
lytic studies of psychosis-proneness scales [3,24,30] or
of other scales [31]. Nevertheless, most studies are based
on measures of schizotypal symptoms given to non- clinical
groups, mostly undergraduates and few studies have done
factor analyses with non-normal samples. However, factor
analyses with schizotypal and other clinical samples also
support a three-dimensional model, though a paranoid
[32,33] or an impulsivity [31] dimension is sometimes
also seen. Although findings differ in detail across ana-
lyses, they appear to converge on the three-factor solution
both in clinical and non-clinical samples. In a theoretical
conceptualization of dimensionality in schizophrenia, a
continuum of be havi ors from normal to schizophrenic was
often suggested (for review see [5]). Strikingly enough, in
accordance with this continuum hypothesis, three-factor
structure was also showed in the low scores sample. In-
terestingly, as with schizophrenia, the evidence for di-
mensionality in schizotypy is primarily found in factor
analytic studies and the three schizotypal dimensions
were close to some schizophrenic dimensions.
Our results suggest that schizotypal traits in a French
non clinical sample, as measured with SPQ, MIS, PAS,
PhA, and SA, are a three-dimensional construct as seen
in schizophrenia itself and in people with Schizotypal
Personality Disorder. Future studies should examine the
stability of those three sch izotyp al di mensions over ti me,
by following schizotypal subjects well into the age of
potential onset of schizophrenia. Moreover, questionnai-
res and structured interviews to measure schizotypal
characteristics may take into acco unt these factors.
This research was supported by grants from the “Progamme Hospi-
talier de Recherche Clinique” (PHRC), the “Université Lyon 1” (BQR)
and the “Conseil Scientifique de la Recherche, CH Le Vinatier”. The
authors are grateful to T.R. Kwapil and A. Raine for their comments
and their agreement about the French versions of their scales; to P.
Dumas for the scales’ translations and to F. Comte for technical help.
[1] Saoud, M., d’Amato, T., Gutknecht, C., Triboulet, P.,
Bertaud, J.P., Marie-Cardine, M., Dalery, J. and Rochet,
T. (2000) Neuropsychological deficit in siblings discor-
dant for schizophrenia. Schizophrenia Bulletin, 26, 893-
[2] Brunelin, J., d’Amato, T., Brun, P., Bediou, B., Kallel, L.,
Senn, M., Poulet, E. and Saoud, M. (2007) Impaired
verbal source monitoring in schizophrenia: An interme-
diate trait vulnerability marker? Schizophrenia Research,
89, 287-292. doi:10.1016/j.schres.2006.08.028
[3] Claridge, C., McCreery, C., Mason, O., Bentall, R., Boyle,
G., Slade, P. and Popplewell, D. (1996) The factor struc-
ture of schizotypal traits: A large replication study. Brit-
ish Journal of Clinical Psychology, 35, 103-115.
[4] Raine, A., Reynolds, C., Lencz, T., Scerbo, A., Triphon,
N. and Kim, D. (1994) Cognitive-perceptual, interper-
sonal, and disorganized features of schizotypal personal-
ity. Schizophrenia Bulletin, 20, 191-201.
[5] Van Os, J. (2003) Is there a continuum of psychotic ex-
periences in the general population? Epidemiologia e
Psichiatria Sociale, 12, 242-252.
[6] Raine, A. (1991) The SPQ: A scale for the assessment of
schizotypal personality based on DSM-III-R criteria.
Schizophrenia Bulletin, 17, 555-564.
[7] Chapman, L.J., Chapman, J.P., Kwapil, T.R., Eckblad,
M.L. and Zinser, M.C. (1994) Putatively psychosis prone
individuals ten years on. Journal of Abnormal Psychol-
ogy, 103, 171-183. doi:10.1037/0021-843X.103.2.171
[8] Van Kampen, D. (2006) The Schizotypic Syndrome
Questionnaire (SSQ): Psychometrics, validation and
norms. Schizophrenia Research, 84, 305-322.
[9] Gruzelier, J.H. (1996) The factorial structure of schizo-
typy: Part I. Affinities with syndromes of schizophrenia.
Schizophrenia Bulletin, 22, 611-620.
[10] Lindenmayer, J.P., Grochowski, S. and Hyman, R.B.
(1995) Five factor model of schizophrenia: Replication
across samples. Schizophrenia Research, 14, 229-234.
[11] Mass, R., Schoemig, T., Hitschfeld, K., Wall, E. and Haasen,
C. (2000). Psychopathological syndromes of schizoph ren ia :
Evaluation of the dimensional structure of the positive
and negative syndrome scale. Schizophrenia Bulletin, 26,
J. Brunelin et al. / Open Journal of Psychiatry 1 (2011) 110-114
Copyright © 2011 SciRes. OJPsych
[12] El Yazaji, M., Battas, O., Agoub, M., Moussaoui, D.,
Gutknecht, C., Dalery, J., d’ Amato, T. and Saoud, M.
(2002) Validity of the depressive dimension extracted
from principal component analysis of the PANSS in drug-
free patients with schizophrenia. Schizophrenia Research,
56, 121-127. doi:10.1016/S0920-9964(01)00247-X
[13] Vollema, M.G., and Hoijtink H. (2000) The multidimen-
sionality of self-report schizotypy in a psychiatric popu-
lation: An analysis using multidimensional Rasch models.
Schizophrenia Bulletin, 26, 565-575.
[14] Gassab, L., Mechri, A. , Dumas, P., Saoud, M., d’ Amato,
T., Dalery, J. and Gaha, L. (2006) Dimensional approach
of schizotypal personality: A comparative study between
French and Tunisian students. Annales Médico-Psycho-
logiques, Revue Psychiatrique, 164, 377-382.
[15] Chen, W.J., Hsiao, C.K. and Lin, C.C.H. (1997) Schi-
zotypy in community samples: The three-factor structure
and correlation with sustained attention. Journal of Ab-
normal Psychology, 106, 649-654.
[16] Fyers, A.J., Endicott, J., Manuzza, S., and Klein, D.F.
(1985) Schedule for affective disorders and schizophre-
nia-life anxiety version. New York State Psychiatric In-
stitute, New York.
[17] Dumas, P., Saoud, M., Bouafia, S., Gutknecht, C., Eco-
chard, R., Dalery, J., Rochet, T. and d’ Amato, T. (2002)
Cannabis use correlates with schizotypal personality traits
in healthy students. Psychiatry Research, 109, 27-35.
[18] Dumas, P., Daléry, J., Saoud, M. and d’ Amato, T. (1999a )
Traductions et adaptations françaises des questionnaires d’
idéation magique [MIS; Eck blad and Chap man 1983] et d’
aberrations perceptives [PAS; Chapman et coll. 1978].
Encephale, 25, 422-428.
[19] Dumas, P., Bouafia, S., Gutknech, C., Saoud, M., Daléry,
J. and d’ Amato, T. (2000a) Validations des versions fr-
ançaises des questionnaires d’ idéation magique [MIS;
Eckblad and Chapman 1983] et d’ aberrations percep-
tives [PAS; Chapman et coll. 1978]. Encephale, 26,
[20] Assouly-Besse, F., Dollfus, S. and Petit, M. (1995) Tra-
duction française des questionnaires d’ anhédonie sociale
et physique de Chapman: Validation de la traduction
française à partir de témoins et de patients schizophrènes.
Encephale, 21, 273-284.
[21] Loas, G., Dubal, S. and Pierson, A. (1996). Dépistage de
l’ anhédonie chez le sujet sain: Détermination des notes-
seuils à l’ échelle révisée d’ anhédonie physique [PAS] de
Chapman et Chapman [1978]. Encephale, 22, 298-302.
[22] Dumas, P., Rosenfeld, F., Saoud, M., Daléry, J. and d’
Amato, T. (1999b) Traduction et adaptation française du
questionnaire de parsonnalité schizotypique de raine
[SPQ]. Encephale, 25, 315-322.
[23] Dumas, P., Bouafia, S., Gutknecht, C., Saoud, M., Daléry,
J. and d’ Amato, T. (2000b) Validation de la version
française du questionnaire de personnalité schizotypique
de Raine [SPQ]—approche catégorielle et dimension-
nelle des traits de personnalité schizotypique en popula-
tion étudiante saine. Encephale, 26, 23-29.
[24] Bentall, R.P., Claridge, G.S. and Slade, P.D. (1989). The
multi-dimensional nature of schizotypal traits: A factor
analytic study with normal subjects. British Journal of
Clinical Psychology, 28, 363-375.
[25] Schiffman, J., Nakamura, B., Earleywine, M. and LaBrie,
J. (2005). Symptoms of schizotypy precede cannabis use.
Psychiatry Research, 134, 37-42.
[26] Vollema, M.G. and van den Bosch, R.J. (1995). The mul-
tidimensionality of schizotypy. Schizophrenia Bulletin,
21, 19-31.
[27] Battaglia, M., Cavallini, M.C., Macciardi, F. and Bellodi,
L. (1997) The structure of DSM-III-R schizotypal disor-
der diagnosed by direct interviews. Schizophrenia Bulle-
tin, 23, 1-10.
[28] Rossi, A. and Daneluzzo, E. (2002) Schizotypal dimen-
sions in normals and schizophrenic patients: A compari-
son with other clinical samples. Schizophrenia Research,
54, 67-75. doi:10.1016/S0920-9964(01)00353-X
[29] Fossati, A., Raine, A., Carretta, I., Leonardi, B. and Maf-
fei, C. (2003) The three-factor model of schizotypal per-
sonality: Invariance across age and gender. Personality
and Individual Differences, 35, 1007-1019.
[30] Suhr, J.A. and Spitznagel, M.B. (2001) Factor versus
cluster models of schizotypal traits: I. A comparison of
unselected and highly schizotypal samples. Schizophre-
nia Research, 52, 231-239.
[31] Mason, O. and Claridge, G. (2006) The Oxford-Liver-
pool Inventory of Feelings and Experiences (O-LIFE):
Further description and extended norms. Schizophrenia
Research, 82, 203-211.
[32] Rosenberger, P.H. and Miller, G.A. (1989) Comparing
borderline definition: DSM-III borderline and schizo-
typal personality disorders. Journal of Abnormal Psy-
chology, 98, 161-169. doi:10.1037/0021-843X.98.2.161
[33] Bergman, A.J., Harvey, P.D., Mitropoulou, V., Aronson,
A., Marder, D., Silverman, J., Trestman, R. and Siever,
L.J. (1996) The factor structure of schizotypal symptoms
in a clinical population. Schizophrenia Bulletin, 22, 501-