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Schizotypal, Dissociative, and Imaginative Processes in a Clinical
OCD Sample
Stella-Marie Paradisis,1,2 Frederick Aardema,1, 2 and Kevin D. Wu3
1Research Centre, Montreal Mental Health University Institute
2University of Montreal
3Department of Psychology, Northern Illinois University
Objective: Previous research in a nonclinical sample has suggested that schizotypal, dissociative,
and imaginative processes may play a role in obsessive-compulsive disorder (OCD) symptoms (Aardema
& Wu, 2011). The present study aims to extend these findings in a clinical sample. Method: N=
75 adults (mean age =37.99; 61.3% female), meeting the Diagnostic and Statistical Manual of Mental
Disorders, Fourth Edition, Text Revision, diagnostic criteria for OCD completed a battery of self-report
questionnaires measuring schizotypal, dissociative, and imaginative processes. Results: Hierarchi-
cal regression analyses revealed inferential confusion and dissociation to be the strongest predictors of
OCD symptoms, replicating and extending the findings by Aardema and Wu (2011). Conclusion: Re-
sults support the notion that inferential confusion and dissociation are important variables to consider
in understanding symptoms of OCD independently from obsessive beliefs and negative mood states.
C2015 Wiley Periodicals, Inc. J. Clin. Psychol. 00:1–19, 2015.
Keywords: schizotypy; imagination; dissociation; inferential confusion; obsessive-compulsive disorder
Obsessive-compulsive disorder (OCD) is a chronic, debilitating mental illness that is charac-
terized by both obsessions (recurrent intrusive thoughts, images, or urges of an unwanted and
persistent nature) and compulsions (ritualistic behaviors or mental acts that an individual feels
compelled to perform to reduce anxiety; American Psychiatric Association [APA], 2013). Al-
though there is a lack of consensus as to the exact ways in which OCD symptoms cluster
together (Calamari et al., 2004), a meta-analysis (Bloch, Landeros-Weisenberger, Rosario, Pit-
tenger, & Leckman, 2008) involving 21 studies and 5,124 people revealed symmetry, cleaning,
hoarding, forbidden thoughts (e.g., aggressive, religious), and checking as common symptom
dimensions. Similarly, Abramowitz and colleagues (2010) found that OCD could be divided into
four symptom dimensions (unacceptable thoughts, symmetry/incompleteness, contamination,
and responsibility for harm and mistakes), while exploratory and confirmatory factor analyses
by Wu and Carter (2008) revealed rituals, impulses, contamination, checking, and hoarding as
common symptom dimensions.
Most cognitive models of OCD claim that it is not the content of intrusive thoughts that deter-
mine whether they develop into obsessions, but the way in which these thoughts are interpreted
according to specific obsessive beliefs (Salkovskis, 1985). Specifically, the cognitive appraisal
model of OCD holds that a “normal” cognition transitions into the realm of obsessions when it
is falsely appraised as being “personally significant, revealing and threatening” (Rachman, 1997,
p. 794). Various underlying beliefs relevant to OCD have been implicated in the transition from
This study was supported by a grant (no. 111261) to Frederick Aardema from the Canadian Institutes for
Health Research (CIHR).
Frederick Aardema is also a recipient of the CIHR New Investigator Award and a research scholar award
from the Quebec Health Research Fund (Fonds de la recherche en sant´
eduQu
´
ebec).
We thank our recruitment coordinator Karine Bergeron for her assistance with the study.
Please address correspondence to: Stella-Marie Paradisis, Research Centre, Montreal Mental Health
University Institute, 7331 Hochelaga, Montr´
eal, Qu´
ebec, H1N 3V2, Canada. E-mail: stella-
marie.paradisis@umontreal.ca
JOURNAL OF CLINICAL PSYCHOLOGY, Vol. 00(0), 1–19 (2015) C2015 Wiley Periodicals, Inc.
Published online in Wiley Online Library (wileyonlinelibrary.com/journal/jclp). DOI: 10.1002/jclp.22173
2 Journal of Clinical Psychology, xxxx 2015
intrusions to obsessions. The Obsessive Beliefs Questionnaire-44 (OBQ-44; Obsessive Compul-
sive Cognitions Working Group [OCCWG], 2005) assesses several beliefs that are relevant to
OCD, including intolerance of uncertainty, perfectionism, overimportance of thoughts, need for
control, overestimation of threat, and inflated responsibility (OCCWG, 2001; 2003).
Subsequent research with the OBQ found a strong overlap in variance among these obsessive
beliefs subscales as well as inconsistent evidence that these beliefs are specific to OCD (Polman,
O’Connor, & Huisman, 2011; Tolin, Woods, & Abramowitz, 2003). Despite these limitations,
obsessive beliefs do appear to predict OCD symptoms independently from anxiety and depres-
sion (Abramowitz, Khandker, Nelson, Deacon, & Rygwall, 2006; OCCWG, 2005). As research
continues to refine the content and measurement of belief domains, this work has the potential
to further our understanding of OCD symptom development.
Another line of research has highlighted inherent characteristics of the obsessions themselves
that might play a role in symptom development (Aardema & Wu, 2011). In other words, rather
than focusing solely on the negative consequences of appraisals of intrusive cognitions, it is also
of interest as to how people with OCD come to accept the premise of the intrusive thought,
especially in obsessions of a more bizarre character. For example, the peculiar nature of some
obsessive thoughts (e.g., I might cause harm with my thoughts) has led some researchers to
believe that schizotypal thinking may play an important role in the development of obsessions
(McKay & Gruner, 2008).
In addition, early clinical research into treatment-resistant OCD noted that individuals who
did not benefit from traditional behavior therapy also presented with elevated levels of investment
into the logic of their obsessive thoughts (Foa, Steketee, Grayson, & Doppelt, 1983; Rachman,
1983). These fixed ideas termed “overvalued ideations” do not derive their content from typical
life experiences and tend to be held with a near delusional level of conviction (O’Connor,
Aardema, & P´
elissier, 2005; Veale, 2002).
Indeed, research has demonstrated a potential connection between OCD and schizotypal
symptoms (Jenike, Baer, Miniciello, Schwartz, & Carey, 1986; Tallis & Shafran, 1997). It is
particularly important to assess the degree of fixity of beliefs in individuals with OCD, as
individuals with poor insight into the irrationality of their symptoms typically do not respond
as well to traditional cognitive-behavioral therapy (Foa, Abramowitz, Franklin, & Kozak, 1999;
Neziroglu, Stevens, Yaryura-Tobias, & McKay, 2001). Sobin and colleagues (2000) found that
half of the participants in a sample of individuals with clinically significant levels of OCD also
demonstrated mild to severe symptoms of schizotypy. Likewise, Muris and Merckelbach (2003)
found that the schizotypal symptom of fantasy proneness was significantly related to symptoms
of OCD.
Furthermore, Tolin, Abramowitz, Kozak, and Foa (2001) found that OCD–schizotypy re-
lations differed by OCD subtype: Individuals with religious or harm-related obsessions (by
impulse or mistake) reported greater levels of perceptual aberrations, magical ideations, and
fixity of belief. A more recent study, however, did not find schizotypal symptoms to be related to
any specific subtypes of OCD, after controlling for dissociation and other imaginative processes,
with the exception of hoarding, which was independently predicted by schizotypy (Aardema &
Wu, 2011).
Related to schizotypal features, the intensity of obsessions has also been noted as a character-
istic potentially operating independently from obsessive beliefs and appraisals. For the individual
with OCD, obsessions may be experienced with “hallucinatory vividness,” making them almost
impossible to dismiss as irrelevant occurrences (Guidano & Liotti, 1983). The strong reality
value and intensity of some obsessions have led researchers to suggest a high level of imaginative
absorption among individuals with OCD. An experimental study found that those with OCD
are more strongly affected by possibility-based information (e.g., “I could have made a mistake”
and “I might have caused someone harm”; Aardema, O’Connor, P´
elissier, & Lavoie, 2009) than
are nonclinical controls.
Despite the fact that the doubting inference is purely a product of an individual’s own
imagination (Aardema, Kleijer, Trihey, O’Connor, & Emmelkamp, 2006) and is both improbable
and unrealistic in the here and now (Aardema et al., 2009; Aardema et al., 2010; O’Connor et al.,
2005), the subjective narrative sustaining the doubt is accorded undue weight (O’Connor, Ecker,
Schizotypy, Dissociation, and Imagination in OCD 3
Lahoud, & Roberts, 2012). In these cases, the subjective narrative overrides reality to the point
that the person with OCD no longer trusts the information available through common sense and
the senses. In other words, the individual’s subjective narrative serves to maintain doubt despite a
lack of reality-based information, indicating that there is reason for the doubt (O’Connor et al.,
2005; O’Connor et al., 2012). According to the inference-based approach (O’Connor et al., 2005)
to OCD, doubting pre-existing sensory or common sense knowledge that all is correct can be
differentiated from true uncertainty, whereby the individual has no prior information on which
to base an evaluation of a given situation (O’Connor, 2014; O’Connor et al., 2005).
It holds that the person with OCD is not so much intolerant to uncertainty as that he or she
creates uncertainty where there should be none. Specifically, an obsessional reasoning process
termed “inferential confusion” is characterized by an overreliance on the imagination and a
distrust of the senses and has been suggested to contribute to OCD symptom development.
Inferential confusion is independent from other cognitive domains, including intolerance of
uncertainty and inflated responsibility (Aardema, Radomsky, O’Connor, & Julien, 2008).
To assess these reasoning processes, Aardema and colleagues (Aardema, O’Connor, Em-
melkamp, Marchand, & Todorov, 2005) developed the Inferential Confusion Questionnaire,
which has been strongly related to symptoms of OCD, independently of other cognitive do-
mains and negative mood states in both nonclinical and clinical samples (Aardema et al., 2005;
Aardema et al., 2006; Aardema et al., 2008). For example, a small-scale clinical study demon-
strated that individuals receiving inference-based therapy, which addresses inferential confusion
in individuals with OCD, had equal treatment outcome as those receiving standard cognitive-
behavioral therapy targeting appraisals (O’Connor et al., 2005). There was evidence for the
treatment to be more effective than standard cognitive-behavioral therapy among those with a
high personal investment in their obsessions. Overall, then, the construct of inferential confusion
has been quite useful for understanding OCD symptom development and informing treatment,
and while not incompatible with appraisal models, it focuses on a different step within the ob-
sessional sequence centered on an overreliance on the imagination during reasoning (Clark &
O’Connor, 2004).
A related type of imaginative process proposed to play a role in symptoms of OCD is dissocia-
tion. Dissociative symptoms significantly relate to symptoms of OCD, especially with respect to
checking compulsions (Grabe et al., 1999; Rufer, Fricke, Held, Cremer, & Hand, 2006; Watson,
Wu, & Cutshall, 2004). In addition, Lochner et al. (2004) classified 15.8% of people with OCD
as high dissociators. Still, most studies investigating the relationship between dissociative symp-
toms and OCD symptoms do not control for general distress. Further, levels of dissociation
in those with OCD are not always higher than those found in anxious controls (Goff, Olin,
Jenike, Baer, & Buttolph, 1992). Some have suggested that individuals with OCD become so
absorbed into their obsessions due to inferential confusion that symptoms of dissociation from
reality may occur (O’Connor et al., 2005). Others have emphasized an OCD-specific variant of
dissociation—a self-related sense of incompleteness that contributes to an “incomplete” recol-
lection of one’s actions, which may in turn account for compulsive behaviors (Ecker & G¨
onner,
2006; Ecker, Kupfer, & G ¨
onner, 2013).
Aims and Hypotheses
Previous research has suggested relations between imaginative, dissociative, and schizotypal pro-
cesses and OCD symptoms. In particular, Aardema and Wu (2011) found inferential confusion
and dissociation to be the most consistent predictors of OCD symptom development. However,
this study was conducted using a nonclinical sample, which limits the generalizability of the
findings to clinical OCD. Also, Aardema and Wu (2011) did not include a measure of obsessive
beliefs, which could potentially account for the relations between schizotypal, dissociative, and
imaginative processes with OCD symptoms. There are currently no studies that have investi-
gated these constructs simultaneously to identify the most crucial variables relevant to OCD.
Specifically, the relations between schizotypal, dissociative, and imaginative processes with OCD
symptoms have yet to be determined in clinical populations and after controlling for other key
4 Journal of Clinical Psychology, xxxx 2015
factors such as negative mood states and obsessive beliefs. The main hypotheses of the current
study are as follows:
H1: Obsessive beliefs, schizotypy, dissociation, and inferential confusion all will relate
significantly to OCD symptoms.
H2: Inferential confusion and dissociation will be the strongest predictors of OCD symptoms,
after controlling for negative mood states and obsessive beliefs.
Table 1
Means, Standard Deviations, Internal Consistency, and Intercorrelations
MSDICQ-EV SPQ DES-II OBQICT OBQPC OBQRT
ICQ-EV 108.07 36.45 .97 .30* .23* .43** .34** .59**
SPQ 19.67 15.00 .96 .39** .01 .30* .34**
DES-II 11.04 10.86 .92 .09 .21 .10
OBQICT 38.49 18.23 .92 .30* .56**
OBQPC 73.85 22.08 .93 .48**
OBQRT 63.89 22.59 .91
Note. M – mean; SD =standard deviation; ICQ-EV =Inferential Confusion Questionnaire-Expanded Ver-
sion; SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; OBQICT =
Obsessive Beliefs Questionnaire-Importance/Control Subscale; OBQPC =Obsessive Beliefs Questionnaire-
Perfectionism/Certainty Subscale; OBQRT =Obsessive Beliefs Questionnaire-Responsibility/Threat Sub-
scale.
N=70–75. Diagonal indicates Cronbach’s alpha.
**Correlation is significant at p<.01. *Correlation is significant at p<.05.
Table 2
Descriptive Statistics for the Symptom Measures and Correlations With the Cognitive Measures
MSDAlpha ICQ-EV SPQ DES-II OBQICT OBQPC OBQRT
VOC I
Total score 68.77 31.37 .92 .46** .39** .48** .22 .51** .47**
Obsessions 9.66 9.91 .90 .42** .21 .45** .45** .21 .37**
Checking 11.74 8.51 .95 .46** .30* .23* .14 .31** .39**
Contamination 12.33 11.08 .92 .43** .10 .24* .01 .16 .22
Indecisiveness 10.04 5.77 .83 .37** .39** .42** .17 .54** .40**
Hoarding 6.96 8.25 .95 -.13 .33** .15 -.29* .21 .00
Just right 18.93 11.36 .89 .36** .39** .50** .08 .51** .32**
YBOCS
Total score 25.67 6.90 .85 .38** .23 .24* .03 .26* .29*
Obsessions 13.00 3.71 .77 .34** .16 .08 .17 .27* .29*
Compulsions 12.67 4.18 .83 .32** .23 .32** -.10 .19 .22
BAI 13.17 9.81 .88 .37** .45** .30** .17 .36** .42**
BDI-II 14.68 9.52 .88 .23* .47** .28* .13 .45** .30*
Note. M - mean; SD =standard deviation; VOCI =Vancouver Obsessional Compulsive Inventory; YBOCS
=Yale-Brown Obsessive-Compulsive Scale; BAI =Beck Anxiety Inventory; BDI-II =Beck Depression
Inventory; ICQ-EV =Inferential Confusion Questionnaire-Expanded Version; SPQ =Schizotypal Person-
ality Questionnaire; DES-II =Dissociative Experiences Scale; OBQICT =Obsessive Beliefs Questionnaire-
Importance/Control Subscale; OBQPC =Obsessive Beliefs Questionnaire-Perfectionism/Certainty Sub-
scale; OBQRT =Obsessive Beliefs Questionnaire-Responsibility/Threat Subscale.
N=70–75.
**Correlation is significant at p<.01. *Correlation is significant at p<.05.
Schizotypy, Dissociation, and Imagination in OCD 5
Table 3 a
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Total Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Total
Step 1 .20 F(2, 63) =8.88 <.001
BAI 0.11 3.74 .01 0.03 .977
BDI-II 10.26 3.66 .47 2.80 .007
Step 2 .32 F(5, 60) =7.19 <.001
BAI −3.24 3.60 −.14 −0.90 .371
BDI-II 8.15 3.52 .37 2.31 .024
OBQ-ICT −1.91 2.61 −.09 −0.73 .467
OBQ-PC 0.33 .17 .24 1.92 .060
OBQ-RT 0.45 .19 .33 2.37 .021
Step 3 .51 F(8, 57) =9.35 <.001
BAI −6.32 3.14 −.28 −2.01 .049
BDI-II 7.54 3.09 .34 2.44 .018
OBQ-ICT −3.31 2.34 −.15 −1.42 .162
OBQ-PC 0.24 0.15 .17 1.59 .118
OBQ-RT 0.29 0.19 .21 1.56 .125
SPQ 0.54 1.85 .03 0.29 .770
DES-II 18.84 6.49 .31 2.90 .005
ICQ-EV 0.29 0.10 .33 2.88 .006
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Total =Vancouver Obsessional
Compulsive Inventory-Total Score; BAI =Beck Anxiety Inventory; BDI-II =Beck Depression Inventory;
OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control Subscale; OBQ-PC =
OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat Subscale; SPQ =Schizo-
typal Personality Questionnaire; DES-II =DissociativeExperiences Scale; ICQ-EV =Inferential Confusion
Questionnaire-Expanded Version.
Method
Participants
Participants were 75 adults meeting the Diagnostic and Statistical Manual of Mental Disorders,
Fourth Edition, Text Revision (DSM-IV-TR; APA, 2000) diagnostic criteria for OCD. Partici-
pants were recruited through existing research programs at the Centre de recherche de l’Institut
universitaire en sant´
e mentale de Montr´
eal. Eligibility was determined using a two-stage assess-
ment process as follows: (a) a standard telephone screening interview based on DSM-IV-TR
criteria for OCD, as well as several other disorders studied at the center (e.g., tic disorder, body
dysmorphic disorder); and (b) a face-to-face diagnostic interview by a trained evaluator who was
independent to the study. The diagnostic interview included three semistructured interviews.
First, all participants were administered the Structured Clinical Interview for DSM-IV Axis
I Disorders, Research Version, Patient Edition (SCID-I/P; First, Spitzer, Gibbon, & Williams,
2002). The SCID-I has “superior validity” (Grabill, Merlo, Duke, Harford, & Storch, 2008) as a
diagnostic tool, according to established standards (Basco et al., 2000), and has good test-retest
reliability (k=.35 to 1.0; Grabill et al., 2008). Second, participants were administered the Yale-
Brown Obsessive-Compulsive Scale (YBOCS; cut-off score ࣙ16; Goodman, Price, Rasmussen,
& Mazure, 1989a,1989b). Third, the SCID for DSM-IV Axis II Personality Disorders (SCID-II;
First, Gibbon, Spitzer, Williams, & Benjamin, 1997; see Maffei et al., 1997, for reliability) was
administered as an assessment of personality dimensions that may have an effect on treatment
engagement, compliance, or outcome (e.g., Dreessen, Hoekstra, & Arntz, 1997; Fals-Stewart &
Lucente, 1993).
6 Journal of Clinical Psychology, xxxx 2015
Table 3 b
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Obsessions Subscale Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Obsessions
Step 1 .15 F(2, 63) =6.51 .003
BAI 0.04 0.06 .12 0.69 .492
BDI-II 0.11 0.06 .32 1.86 .068
Step 2 .28 F(5, 60) =6.12 <.001
BAI 0.02 0.06 .05 0.28 .777
BDI-II 0.12 0.06 .34 2.06 .044
OBQ-ICT 0.13 0.04 .37 3.01 .004
OBQ-PC −0.00 0.00 −.13 −1.02 .310
OBQ-RT 0.00 0.00 .11 0.81 .423
Step 3 .39 F(8, 57) =6.10 <.001
BAI −0.02 0.06 −.06 −0.41 .683
BDI-II 0.12 0.06 .33 2.12 .038
OBQ-ICT 0.11 0.04 .31 2.55 .014
OBQ-PC −0.00 0.00 −.19 −1.59 .118
OBQ-RT 0.00 0.00 .10 0.61 .541
SPQ −0.02 0.03 −.08 −0.64 .523
DES-II 0.31 0.11 .33 2.76 .008
ICQ-EV 0.00 0.00 .19 1.50 .139
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Obsessions =Vancouver Ob-
sessional Compulsive Inventory-Obsessions Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck
Depression Inventory; OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control
Subscale; OBQ-PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat
Subscale; SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-
EV =Inferential Confusion Questionnaire-Expanded Version.
Entry criteria for the study are as follows: (a) a primary diagnosis of OCD; (b) no change
in medication type or dose during the 12 weeks before treatment for antidepressants (4 weeks
for anxiolytics); (c) willingness to keep medication stable while participating in the study; (d)
no evidence of suicidal intent; (e) no evidence of current substance abuse; and (f) no evidence
of current or past schizophrenia, bipolar, or organic mental disorder. After the assessment,
participants completed a battery of questionnaires. For their participation, eligible participants
received 24 weeks of inference-based therapy for OCD (4 weeks of evaluation and 20 weeks of
treatment) free of charge. The sample comprised 61.3% women and had a mean age of 38.0 years
(standard deviation [SD]=12.8; range from 17 to 66 years).
Questionnaires
The YBOCS (Goodman et al., 1989a,b) is a clinician-administered semistructured interview that
is considered to be the “gold standard” assessment for OCD symptom severity (Frost, Steketee,
Krause, & Trepanier, 1995). The YBOCS produces three severity scores: obsessions (five items),
compulsions (five items), and total score (10 items). Responses were rated on a 5-point scale
ranging from 0 (not at all)to4(extreme), Grabill et al. (2008) reported that this test is sensitive
to treatment change and has adequate internal consistency (α=.69–.91).
The Vancouver Obsessional Compulsive Inventory (VOCI; Thordarson et al., 2004) is a 55-
item self-report questionnaire that assesses OCD symptom severity. This questionnaire was
selected due to its distinct advantage of measuring both cognitive and behavioral dimen-
sions of OCD (Grabill et al., 2008). Symptom severity is scored on six subscales: obsessions,
indecisiveness, just right, contamination, hoarding, and checking, using a 5-point scale ranging
Schizotypy, Dissociation, and Imagination in OCD 7
Table 3 c
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Checking Subscale Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Checking
Step 1 .03 F(2, 63) =1.95 .151
BAI 0.13 1.14 .02 0.11 .911
BDI-II 1.38 1.11 .23 1.24 .221
Step 2 .11 F(5, 60) =2.60 .034
BAI −0.81 1.15 −.13 −0.71 .479
BDI-II 1.09 1.12 .18 0.97 .334
OBQ-ICT −0.76 0.83 −.13 −0.91 .365
OBQ-PC 0.05 0.06 .12 0.84 .406
OBQ-RT 0.14 0.06 .37 2.36 .022
Step 3 .21 F(8, 57) =3.18 .005
BAI −1.35 1.10 −.22 −1.24 .222
BDI-II 1.04 1.08 .17 0.96 .339
OBQ-ICT −1.07 0.82 −.18 −1.31 .196
OBQ-PC 0.03 0.05 .08 0.61 .546
OBQ-RT 0.07 0.07 .18 1.08 .287
SPQ 0.37 0.65 .08 0.58 .567
DES-II 1.32 2.27 .08 0.58 .562
ICQ-EV 0.10 0.04 .40 2.76 .008
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Checking =Vancouver Obses-
sional Compulsive Inventory-Checking Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck Depres-
sion Inventory; OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control Subscale;
OBQ-PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat Subscale;
SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-EV =Infer-
ential Confusion Questionnaire-Expanded Version.
from 0 (not at all)to4(very much). The VOCI has demonstrated good psychometric properties,
including strong internal consistency (α=.94 total; α=.88–.96 for the subscales; Grabill et al.,
2008; Thordarson et al., 2004).
The OBQ-44 (OCCWG, 2005) is a 44-item self-report measure that assesses belief domains
in clinical and nonclinical populations. The level of agreement with each statement is rated on a
7-point scale ranging from 1 (disagree very much)to7(agree very much). The OBQ-44 comprises
three underlying factors: responsibility/threat estimation (RT), perfectionism/certainty (PC),
and importance/control of thoughts (ICT; OCCWG, 2005). Internal consistency generally is
strong (αs range from .90–.93; Tolin, Worhunsky, & Maltby, 2006).
The Dissociative Experiences Scale (DES-II; Carlson & Putnam, 1993) is a 28-item self-report
measure that assesses the frequency of dissociation in clinical and nonclinical populations.
Responses are rated on an 11-point scale (0 to 100, increasing by increments of 10). The overall
score is obtained by adding up the 28 item scores and dividing by 28: This yields an overall score
ranging from 0 to 100. The DES-II comprises three underlying factors: amnesic dissociation,
absorption/imaginative involvement, and depersonalization/derealization (Carlson et al., 1991).
Reliability varies between α=.93 (Van IJzendoorn & Schuengel, 1996) and .95 (Frischholz et al.,
1990).
Inferential Confusion Questionnaire-Expanded Version (ICQ-EV; Aardema et al., 2010) is
a 30-item self-report questionnaire that measures the propensity of individuals with OCD to
distrust their senses and confound the imaginary nature of their obsessions with reality due
to faulty reasoning processes. Responses are rated on a 6-point scale ranging from 1 (strongly
disagree)to6(strongly agree), with elevated scores indicating a distrust of the senses and
8 Journal of Clinical Psychology, xxxx 2015
Table 3 d
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Contamination Subscale Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Contamination
Step 1 −.03 F(2, 63) =.12 .891
BAI 0.12 0.25 .09 0.46 .649
BDI-II −0.06 0.25 −.05 −0.24 .811
Step 2 −.01 F(5, 60) =.84 .527
BAI −0.02 0.26 −.02 −0.08 .939
BDI-II −0.09 0.26 −.07 −0.36 .724
OBQ-ICT −0.24 0.19 −.19 −1.26 .212
OBQ-PC 0.01 0.01 .08 0.52 .607
OBQ-RT 0.02 0.01 .28 1.63 .108
Step 3 .19 F(8, 57) =2.93 .008
BAI −0.18 0.24 −.14 −0.76 .448
BDI-II −0.06 0.24 −.04 −0.23 .816
OBQ-ICT −0.38 0.18 −.30 −2.15 .036
OBQ-PC 0.00 0.01 .02 0.17 .867
OBQ-RT 0.01 0.01 .10 0.55 .582
SPQ −0.07 0.14 −.07 −0.49 .629
DES-II 0.73 0.50 .20 1.47 .148
ICQ-EV 0.03 0.01 .51 3.47 .001
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Contamination =Vancouver
Obsessional Compulsive Inventory-Contamination Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck
Depression Inventory; OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control
Subscale; OBQ-PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat
Subscale; SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-
EV =Inferential Confusion Questionnaire-Expanded Version.
overreliance on the imagination. Internal consistency varies between α=.96 in nonclinical
samples and .97 in clinical samples (Aardema et al., 2010).
Schizotypal Personality Questionnaire (SPQ; Raine, 1991) is a self-report questionnaire based
on the DSM, Third Edition, Revised (DSM-III-R; APA, 1987) criteria. The SPQ assesses each
of the nine features of schizotypal personality disorder that correspond to three broad symptom
categories: positive or cognitive perceptual symptoms (e.g., distorted perception); negative or
interpersonal symptoms (e.g., lack of friends); and disorganized symptoms (e.g., bizarre speech
patterns). This questionnaire has been previously used in OCD-relevant research (Moritz et al.,
2004) and has good internal consistency (α=.91; Raine, 1991).
Beck Depression Inventory-II (BDI-II; Beck, Steer, & Brown, 1996)is a 21-item self-report
questionnaire that assesses symptoms of major depression. Each item is rated on a severity scale
ranging from 0 to 3 for a maximum score of 63. The BDI has good internal consistency (α=
.91; Dozois, Dobson, & Ahnberg, 1998).
Beck Anxiety Inventory (BAI; Beck, Epstein, Brown, & Steer, 1996) is a 21-item self-report
questionnaire that assesses symptoms of anxiety. Each item is rated on a severity scale ranging
from 0 to 3 for a maximum score of 63. The BAI has good internal consistency (α=.92; Beck
et al., 1988).
Results
Data were analysed using IBM SPSS (version 16). Before correlationalanalyses, all questionnaire
scores were checked for normality. Logarithmic transformations were performed for the DES-II
Schizotypy, Dissociation, and Imagination in OCD 9
Table 3 e
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Indecisiveness Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Indecisiveness
Step 1 .20 F(2, 63) =8.89 <.001
BAI −0.57 0.71 −.13 −0.80 .430
BDI-II 2.35 0.70 .56 3.36 .001
Step 2 .36 F(5, 60) =8.41 <.001
BAI −1.20 0.67 −.28 −1.80 .077
BDI-II 1.81 0.65 .43 2.77 .007
OBQ-ICT −0.40 0.48 −.10 −0.83 .409
OBQ-PC 0.09 0.03 .33 2.72 .009
OBQ-RT 0.08 0.04 .30 2.26 .028
Step 3 .43 F(8, 57) =7.21 <.001
BAI −1.61 0.64 −.38 −2.51 .015
BDI-II 1.65 0.63 .39 2.61 .012
OBQ-ICT −0.52 0.48 −.12 −1.08 .286
OBQ-PC 0.08 0.03 .28 2.43 .018
OBQ-RT 0.06 0.04 .23 1.56 .124
SPQ 0.23 0.38 .07 0.61 .543
DES-II 2.57 1.33 .22 1.93 .058
ICQ-EV 0.03 0.02 .19 1.52 .135
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Indecisiveness =Vancouver
Obsessional Compulsive Inventory-Indecisiveness Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck
Depression Inventory; OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control
Subscale; OBQ-PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat
Subscale; SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-
EV =Inferential Confusion Questionnaire-Expanded Version.
as well as the VOCI Obsessions and Hoarding subscales, while square root transformations were
performed on the VOCI Contamination subscale, the OBQ ICT subscale, the BAI, the BDI,
and the SPQ. Analyses involving the subscales of the DES-II and SPQ were not included due to
excessive skewness after transformations.
Means, Standard Deviations, and Intercorrelations
Means, standard deviations, and intercorrelations among the cognitive measures are reported
in Table 1. All of the scales showed internal consistency values between .91 and .97. In gen-
eral, measures demonstrated low to moderate intercorrelations as well as an adequate level of
discriminant validity.
Schizotypy, Dissociation, Cognitive Domains, and OCD Symptoms
The relations among relevant variables, negative mood states, and OCD symptoms are reported
in Table 2. Coefficient alpha values ranged from .77 to .95. Overall, the ICQ-EV, the SPQ, and
the DES-II demonstrated significant correlations with the VOCI total and subscales, with the
exception of hoarding for the ICQ-EV and DES-II and contamination and obsessions for the
SPQ. Similar results were demonstrated with the YBOCS, with the exception of the SPQ and
obsessions for the DES-II. All measures also demonstrated significant relations with the BAI
and the BDI; the SPQ demonstrated a stronger relationship to these negative mood states than
to OCD symptoms.
10 Journal of Clinical Psychology, xxxx 2015
Table 3 f
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Hoarding Subscale Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Hoarding
Step 1 .17 F(2, 63) =7.44 .001
BAI −0.17 0.07 −.45 −2.68 .009
BDI-II 0.24 0.06 .65 3.85 <.001
Step 2 .29 F(5, 60) =6.38 <.001
BAI −0.19 0.06 −.50 −3.03 .004
BDI-II 0.23 0.06 .62 3.80 <.001
OBQ-ICT −0.17 0.05 −.45 −3.66 .001
OBQ-PC 0.00 0.00 .16 1.22 .226
OBQ-RT 0.00 0.00 .18 1.24 .218
Step 3 .33 F(8, 57) =4.96 <.001
BAI −0.20 0.06 −.53 −3.23 .002
BDI-II 0.20 0.06 .53 3.21 .002
OBQ-ICT −0.14 0.05 −.38 −3.00 .004
OBQ-PC 0.00 0.00 .14 1.11 .271
OBQ-RT 0.00 0.00 .13 0.84 .403
SPQ 0.08 0.04 .28 2.21 .031
DES-II 0.05 0.13 .04 0.35 .728
ICQ-EV −0.00 0.00 −.08 −0.58 .561
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Hoarding =Vancouver Obses-
sional Compulsive Inventory-Hoarding Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck Depres-
sion Inventory; OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control Subscale;
OBQ-PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat Subscale;
SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-EV =Infer-
ential Confusion Questionnaire-Expanded Version.
Predicting OCD Symptoms and Subtypes
To assess the relative contribution of each variable in the prediction of OCD symptoms, we
performed hierarchical regressions to predict scores on both the VOCI (Tables 3a–g) and the
YBOCS (Tables 4a–c) while controlling for the OBQ subscales, the BAI, and the BDI scores.
ThefirstregressionpredictedtheVOCItotalscore.Instep1,weenteredtheBAIandthe
BDI. Collectively, they explained approximately 20% of the variance in overall OCD symptoms,
R2=.20; F(2, 63) =8.88, p<.001, with the BDI as the only significant predictor. In step 2, we
entered the three OBQ subscales; together, they significantly augmented the portion of explained
variance to 32%, R2=.32; F(5, 60) =7.19, p<.001. In this case, the association between factors
is due to the BDI and the OBQRT. The OBQPC subscale approached significance (p=.06).
Finally, in step 3, we entered the ICQ-EV, the SPQ, and the DES-II, and their addition increased
the amount of explained variance for this model to 51%, R2=.51; F(8, 57) =9.35, p<.001. The
most significant predictors at this step were the DES-II and the ICQ-EV, followed by the BAI
and the BDI. Neither the OBQ subscales nor the SPQ emerged as a significant predictor in this
step.
The six remaining hierarchical regressions were conducted in the same fashion to determine
whether there were differences in how each variable related to specific OCD symptom dimensions
(see Tables 3b–g). Results indicated unique patterns of predictors for each OCD symptom
dimension. Specifically, for the obsessions subscale, the strongest predictor was the DES-II,
followed by the OPQICT and the BDI-II. For checking, the only significant predictor was
the ICQ-EV. For contamination, the strongest predictors were the ICQ-EV and the OBQICT.
For indecisiveness, the most significant predictors were the BAI and the BDI-II, followed by the
Schizotypy, Dissociation, and Imagination in OCD 11
Table 3 g
Hierarchical Regressions Predicting Overall Symptoms and Subtypes of OCD as Measured by the
VOCI Just Right Subscale Score (Controlling for OBQ-44 Subscales)
BSE Adj. R2βTest statistic pvalue
Predicting VOCI-Just Right
Step 1 .17 F(2, 63) =7.64 .001
BAI 0.29 1.39 .04 0.21 .834
BDI-II 3.35 1.37 .42 2.46 .017
Step 2 .29 F(5, 60) =8.25 <.001
BAI −0.43 1.35 −.05 −0.32 .752
BDI-II 2.23 1.32 .28 1.69 .097
OBQ-ICT −1.35 0.98 −.17 −1.37 .176
OBQ-PC 0.19 0.07 .38 2.94 .005
OBQ-RT 0.08 0.07 .16 1.14 .260
Step 3 .46 F(8, 57) =7.89 <.001
BAI −1.54 1.20 −.19 −1.28 .206
BDI-II 1.94 1.19 .24 1.64 .108
OBQ-ICT −1.78 0.90 −.22 −1.98 .052
OBQ-PC 0.16 0.06 .31 2.73 .008
OBQ-RT 0.03 0.07 .05 0.36 .720
SPQ 0.33 0.71 .05 0.47 .640
DES-II 6.93 2.49 .31 2.78 .007
ICQ-EV 0.10 0.04 .30 2.48 .016
Note. OCD =obsessive-compulsive disorder; SE =standard error; VOCI-Just Right =Vancouver Ob-
sessional Compulsive Inventory-Just Right Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck
Depression Inventory; OBQ =Obsessive Beliefs Questionnaire; OBQ-ICT =OBQ-Importance/Control
Subscale; OBQ-PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat
Subscale; SPQ =Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-
EV =Inferential Confusion Questionnaire-Expanded Version.
OBQPC, with the DES-II approaching significance (p=.058). For hoarding, the most significant
predictors were the BAI and BDI-II, followed by the OBQICT and the SPQ. Finally, for the
“just right” subscale, the most significant predictors were the DES-II and the OBQPC, followed
by the ICQ-EV; the OBQICT approached significance (p=.052).
A second set of regressions was conducted to predict YBOCS scores (see Tables 4a–c).
As with the previous regressions, the BAI and the BDI-II were entered in step 1, followed
by the three OBQ subscales in step 2, and finally the ICQ-EV, the SPQ, and the DES-II in
step 3. For the YBOCS total score, the strongest predictor was the ICQ-EV; the OBQICT
approached significance (p=.054). For the YBOCS obsessions scale, none of the models from
the analyses yielded statistically significant results, rendering the coefficients uninterpretable.
However, results of the YBOCS compulsions scale revealed the OCQICT, the DES-II, and the
ICQ-EV to be significant predictors. Hence, despite the lack of detailed information regarding
specific symptom subtypes, the hierarchical regressions with the YBOCS demonstrated the
relevance of the inferential confusion and dissociation to OCD symptoms.
Discussion
The current study aimed to investigate how schizotypal, dissociative, and imaginative processes
were relevant to predicting OCD symptoms. Previous research has found these processes to be
related to OCD symptoms, but few studies controlled for negative mood states and the overlap
between measures. Further, many previous studies targeted nonclinical samples. In contrast,
12 Journal of Clinical Psychology, xxxx 2015
Table 4 a
Hierarchical Regressions Predicting Overall Symptoms and Subscales of OCD as Measured by the
YBOCS Total Score (controlling for OBQ-44 subscales)
BSE Adj. R2βTest statistic pvalue
Predicting YBOCS-Total
Step 1 .04 F(2, 64) =2.37 .102
BAI 1.59 0.91 .32 1.75 .086
BDI-II −0.39 0.89 −.08 −0.44 .662
Step 2 .08 F(5, 61) =2.20 .065
BAI 1.13 0.93 .22 1.21 .232
BDI-II −0.73 0.92 −.15 −0.79 .431
OBQ-ICT −1.07 0.68 −.22 −1.57 .122
OBQ-PC 0.06 0.05 .20 1.37 .176
OBQ-RT 0.07 0.05 .23 1.43 .158
Step 3 .14 F(8, 58) =2.33 .030
BAI 0.75 0.92 .15 0.81 .420
BDI-II −0.69 0.91 −.14 −0.76 .452
OBQ-ICT −1.35 0.69 −.28 −1.97 .054
OBQ-PC 0.05 0.04 .17 1.16 .252
OBQ-RT 0.03 0.05 .10 0.59 .560
SPQ −0.01 0.54 −.00 −0.01 .990
DES-II 1.61 1.60 .13 1.01 .317
ICQ-EV 0.06 0.03 .32 2.19 .032
Note. OCD =obsessive-compulsive disorder; SE =standard error; YBOCS-Total =Yale-Brown Obsessive-
Compulsive Scale-Total Score; BAI =Beck Anxiety Inventory; BDI-II =Beck Depression Inven-
tory; OBQ-ICT =Obsessive Beliefs Questionnaire-Importance/Control Subscale; OBQ-PC =OBQ-
Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat Subscale; SPQ =Schizotypal
Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-EV =Inferential Confusion
Questionnaire-Expanded Version.
the current study allowed for the identification of the unique contributions of schiztotypal,
dissociative, and imaginative processes within a clinical sample, after controlling for negative
mood states and multiple obsessive belief domains.
Results showed that imaginative, dissociative, and schizotypal processes were significantly
correlated with each other confirming previous findings. These processes were also significantly
associated with obsessive beliefs; the exception was dissociation, which did not correlate signifi-
cantly with any obsessive belief subscale. Inferential confusion and dissociative experiences were
most strongly related to OCD symptoms, replicating previous findings from a nonclinical sample
(Aardema & Wu, 2011). These measures, however, also related significantly to negative mood
states and other obsessive belief domains, suggesting that their relations with OCD symptoms
could be explained in part by a general overlap in variance with these factors.
To further investigate the unique contributions of schizotypal, dissociative, and imaginative
processes to OCD after controlling for negative mood states and obsessive beliefs, two sets of
hierarchical regressions were performed. Consistent with hypotheses, the strongest predictors for
overall OCD symptoms were inferential confusion and dissociative experiences, when predicting
either the VOCI or the Y-BOCS. These findings are consistent with the notion that individuals
with OCD may become so absorbed into their obsessions that a certain degree of detachment
and derealization from reality may occur (O’Connor & Aardema, 2003).
In terms of specific OCD symptoms, different patterns of predictors emerged. For example, in-
ferential confusion explained a significant amount of the variance for checking, contamination,
and “just right” experiences. In these cases, individuals with OCD may become so involved in
their imagination and subjective narratives that they come to distrust reality-based information
Schizotypy, Dissociation, and Imagination in OCD 13
Table 4 b
Hierarchical Regressions Predicting Overall Symptoms and Subscales of OCD as Measured by the
YBOCS Obsessions Subscale Score (Controlling for OBQ-44 subscales)
BSE Adj. R2βTest statistic pvalue
Predicting YBOCS-Obsessions
Step 1 .07 F(2, 64) =3.42 .039
BAI 0.86 0.48 .32 1.78 .080
BDI-II −0.03 0.47 −.01 −0.05 .957
Step 2 .06 F(5, 61) =1.82 .122
BAI 0.72 0.51 .27 1.42 .162
BDI-II −0.10 0.50 −.07 −0.40 .694
OBQ-ICT −0.01 0.37 −.00 −0.02 .982
OBQ-PC 0.03 0.03 .16 1.09 .282
OBQ-RT 0.01 0.03 .08 0.51 .611
Step 3 .05 F(8, 58) =1.46 .192
BAI 0.66 0.52 .24 1.27 .209
BDI-II −0.14 0.51 −.05 −0.28 .782
OBQ-ICT −0.10 0.39 −.04 −0.26 .799
OBQ-PC 0.03 0.03 .16 1.04 .302
OBQ-RT −0.01 0.03 −.03 −0.18 .858
SPQ 0.01 0.31 .00 0.03 .977
DES-II −0.47 0.90 −.07 −0.52 .607
ICQ-EV 0.03 0.02 .25 1.59 .116
Note. OCD =obsessive-compulsive disorder; SE =standard error; YBOCS- Obsessions =Yal e -Bro wn
Obsessive-Compulsive Scale-Obsessions Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck Depres-
sion Inventory; OBQ-ICT =Obsessive Beliefs Questionnaire-Importance/Control Subscale; OBQ-PC =
OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat Subscale; SPQ =Schizo-
typal Personality Questionnaire; DES-II =DissociativeExperiences Scale; ICQ-EV =Inferential Confusion
Questionnaire-Expanded Version.
provided by their senses or common sense (O’Connor et al., 2005). This would lead them to
continue performing their rituals because they are unable to process information indicating that
all is well and that no action needs to be taken. For “just right” experiences in particular, the
person with OCD may be driven to rectify an inner discomfort or self-related feeling of incom-
pleteness (Ecker et al., 2013) by performing actions in the real world (Coles, Frost, Heimberg,
&Rh
´
eaume, 2003; Coles, Heimberg, Frost, & Steketee, 2005).
Dissociation, on the other hand, was a strong predictor for obsessions, indecisiveness, and
“just right” experiences as measured by the VOCI. In addition, dissociation was a significant
predictor of compulsions as measured by the Y-BOCS. As noted, experiences of dissociation
are often related to imaginative absorption because becoming overly involved in one’s obses-
sions can lead to depersonalization and derealisation from real-life experiences. In the case of
“just right” experiences, Ecker and colleagues (Ecker & G¨
onner, 2006; Ecker et al., 2013) have
suggested that individuals with OCD may experience feelings of self-related incompleteness or
depersonalisation with regard to their actions, leading to repetition of compulsive behaviors.
Still, the current design does not provide direct evidence for causal explanations on the
role of dissociation in OCD. Whereas results are consistent with the idea that dissociation
could give rise to or exacerbate OCD symptoms, it is also possible that dissociation is a mere
consequence of having OCD, in which, for example, severity of symptoms gives rise to elevated
levels of dissociation. The specificity of dissociation to particular subtypes of OCD appears to
suggest that the relationship is due to more than symptom severity alone, but future research
may wish to focus on clarifying the causal pathways in which dissociation relates to symptoms
of OCD.
14 Journal of Clinical Psychology, xxxx 2015
Table 4 c
Hierarchical Regressions Predicting Overall Symptoms and Subscales of OCD as Measured by the
YBOCS Compulsions Subscale Score (Controlling for OBQ-44 subscales)
BSE Adj. R2βTest statistic pvalue
Predicting YBOCS-Compulsions
Step 1 -.00 F(2, 64) =.92 .404
BAI 0.73 0.57 .24 1.28 .206
BDI-II −0.37 0.56 −.12 −0.65 .515
Step 2 .09 F(5, 61) =2.31 .055
BAI 0.41 0.57 .13 0.71 .481
BDI-II −0.53 0.56 −.17 −0.94 .349
OBQ-ICT −1.06 0.42 −.35 −2.55 .013
OBQ-PC 0.04 0.03 .18 1.27 .210
OBQ-RT 0.06 0.03 .30 1.88 .065
Step 3 .21 F(8, 58) =3.20 .005
BAI 0.09 0.54 .03 0.16 .872
BDI-II −0.55 0.54 −.18 −1.02 .311
OBQ-ICT −1.26 0.41 −.42 −3.10 .003
OBQ-PC 0.03 0.03 .13 0.97 .337
OBQ-RT 0.04 0.03 .19 1.17 .247
SPQ −0.02 0.32 −.01 −0.05 .961
DES-II 2.08 0.94 .27 2.21 .031
ICQ-EV 0.04 0.02 .31 2.20 .032
Note. OCD =obsessive-compulsive disorder; SE =standard error; YBOCS- Obsessions =Yal e -Br o wn
Obsessive-Compulsive Scale-Compulsions Subscale; BAI =Beck Anxiety Inventory; BDI-II =Beck De-
pression Inventory; OBQ-ICT =Obsessive Beliefs Questionnaire-Importance/Control Subscale; OBQ-
PC =OBQ-Perfectionism/Certainty Subscale; OBQ-RT =OBQ-Responsibility/Threat Subscale; SPQ =
Schizotypal Personality Questionnaire; DES-II =Dissociative Experiences Scale; ICQ-EV =Inferential
Confusion Questionnaire-Expanded Version.
Finally, schizotypy only contributed unique variance to hoarding. These results are incon-
sistent with previous findings reporting that schizotypy was specifically relevant to obsessions
(Tolin et al., 2001). These results are consistent with previous findings by Aardemaand Wu (2011)
as well as Frost and colleagues (Frost, Steketee, Williams, & Warren, 2000), who found that in-
dividuals with hoarding and nonhoarding OCD differed on schizotypal traits, and Fromm’s
(1947) observation that those with a “hoarding orientation” were more likely to be inhibited
and distant, displaying greater social anxiety and schizotypal traits (Frost et al., 2000; Samuels
et al., 2002; Steketee & Frost, 2003; Steketee, Frost, Wincze, Greene, & Douglas, 2000).
It is interesting to note that obsessive beliefs regarding importance/control of thoughts
emerged as a significant predictor for obsessions, contamination, hoarding, and “just right”
experiences. It makes theoretical sense and is consistent with empirical evidence that
importance/control of thoughts would relate to obsessive thoughts. According to the appraisal
model (OCCWG, 1997), intrusive thoughts that are considered to be distressing by an individual
with OCD are often assigned abnormally high levels of importance, leading them to attempt to
control or rid themselves of these thoughts through various compulsive rituals (Aardema, et al.,
2013; Moulding, Aardema, & O’Connor, 2014). The fact that importance/control of thoughts
emerged as a significant negative predictor for both hoarding and “just right” experiences also
makes theoretical sense, as these individuals tend to have poor insight and may therefore not
feel the need to suppress, censure, or dispel their obsessive thoughts (Coles et al., 2005; Ecker
et al., 2013; Freeston & Ladouceur, 1997; OCCWG, 2005).
Schizotypy, Dissociation, and Imagination in OCD 15
Limitations
This study has several limitations that require consideration. First, the sample size was adequate
but modest, and replication in a larger clinical sample is warranted. Second, this study used
three specific measures of schizotypal, dissociative, and imaginative processes. By including
different measures of these processes, we may potentially expand the explanatory power of
cognitive domains in OCD. Finally, although these results provide us with a more comprehensive
understanding of the roles of schizotypal, dissociative, and imaginative processes in OCD, future
investigations should examine how these processes relate to treatment outcome. By continuing
to investigate the relations between these factors and OCD, future research will further improve
our conceptualization and understanding of OCD, as well as improve treatment outcome.
Conclusion
Overall, inferential confusion and dissociation significantlycontributed to the prediction of OCD
symptoms in this clinical sample, beyond the variance explained by other cognitive domains and
negative mood states. These results lend further support to an inference-based conceptualization
of OCD (Aardema et al., 2008; O’Connor et al., 1997). By examining the relative contributions of
each factor in an OCD sample and in combination with other relevant cognitive belief domains,
these results replicate and extend findings by Aardema and Wu (2011) while addressing several
of that study’s limitations.
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