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Do measures of schizotypal personality provide non-clinical analogues of
schizophrenic symptomatology?
Mary Cochrane, Ian Petch, Alan D. Pickering c
Article history:
Received 16 October 2008
Received in revised form 24 January 2009
Accepted 26 January 2009
This study tested the assumption that measures of schizotypal personality provide non-clinical analogues of
the heterogeneous symptomatology found in the schizophrenic disorder. The Oxford-Liverpool Inventory of
Feelings and Experiences (O-LIFE) was administered to schizophrenic patients and healthy controls, and
measures of symptomatology from the Scale for the Assessment of Positive Symptoms (SAPS) and the Scale
for the Assessment of Negative Symptoms (SANS) were assessed in the patient group. Schizophrenic patients
scored significantly higher than controls on O-LIFE measures of positive, negative and disorganised
schizotypy, while no difference in Impulsive Nonconformity was observed. In the patient group, SAPS
positive symptomatology was significantly correlated with O-LIFE positive schizotypy (Unusual Experiences)
and Cognitive Disorganisation. However, there was no significant relationship between SAPS/SANS
disorganisation and O-LIFE Cognitive Disorganisation, or between the SANS negative factor score and OLIFE
Introvertive Anhedonia. The results suggest that the O-LIFE is a valid tool for assessing schizotypal
personality in both schizophrenic patients and healthy controls. However, while the O-LIFE measure of
positive schizotypy may correspond with SAPS/SANS positive schizophrenic symptomatology, the negative
and disorganised subscales may not be analogous to their SAPS/SANS counterparts. There is also evidence to
question the acceptability of Impulsive Nonconformity as a true schizophrenia-like construct.
© 2009 Elsevier Ireland Ltd. All rights reserved.
1. Introduction
Contemporary authors generally conceptualise schizophrenia and
other psychopathological disorders as extreme forms of disease processes.
The quasi-dimensional approach stems from the psychiatric
perspective and focuses on illness; specifically, the degrees of expression
of a disease (Rado, 1953;Meehl, 1966). The fully dimensional approach
incorporates the quasi-dimensional viewof continuity, but also extends
the continuity to include the healthy personality, which provides the
starting point for the model. Thus, advocates of this model propose that
the dimension of schizotypy lies on a continuum that begins with
normality and proceeds towards the schizophrenia spectrum disorders,
with schizophrenia at the upper end (Claridge and Beech, 1995).
A growing body of evidence has emerged to support the fully
dimensional (or continuum) model of schizophrenia. Individuals high
in schizotypal personality exhibit a range of cognitive and executive
deficits (Peters et al., 1994; Park et al., 1995; Tsakanikos and Claridge,
2005)which are also found in schizophrenic patients (Beech et al.,1989;
Liddle and Morris, 1991; Park and Holzman, 1992). Furthermore, the
heterogeneous positive, negative and disorganised symptom subtypes
found in schizophrenia (Liddle,1987; Arndt et al.,1991) are also found in
schizotypal personality (Raine et al., 1991; Chen et al., 1997).
Some authors report the presence of four schizotypal characteristics;
namely the traditional positive, negative and disorganised
factors and a fourth factor known as Impulsive Nonconformity
(ImpNon) (Mason et al., 1995; Vollema and van den Bosch, 1995).
However, Pickering (2004) argues that ImpNon is not a true
schizotypal factor because it does not reflect cognitions or behaviours
found in schizophrenia. Rather, ImpNon is more reminiscent of the
impulsive, antisocial, sensation-seeking (ImpASS) traits found in
certain personality disorders, such as borderline, schizoid or antisocial
personality disorders. High ImpNon scores are not found in the
relatives of schizophrenic patients (Claridge et al., 1983) and high
ImpNon scores in healthy individuals do not significantly predict
increased risk of psychosis (Chapman et al., 1994).