Cognitive Behavioral Therapy for Negative Symptoms

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Cognitive Behavioral Therapy for negative symptoms (CBT-n) in

psychotic disorders: A pilot study

Anton B.P. Staring a,*, Mary-Ann B. ter Huurne b, Mark van der Gaag c,d

aAltrecht Psychiatric Institute, ABC-straat 8, 3512 PX Utrecht, The Netherlandsb Mediant Psychiatric Institute, Laan van Driene 101, 7552 EN Hengelo, The Netherlandsc Parnassia Psychiatric Institute, Oude Haagweg 357, 2552 ES The Hague, The Netherlandsd VU University and EMGO Institute for Health and Care Research, Van Boechorststraat 1, 1081 BT Amsterdam, The Netherlands

a r t i c l e i n f o

Article history:

Received 1 September 2012

Received in revised form

21 January 2013

Accepted 23 January 2013

Keywords:

Psychosis

Schizophrenia

Cognitive therapy

CBT

Negative symptoms

Self-stigma

a b s t r a c t

Background and objectives:The treatment of negative symptoms in schizophrenia is a major challenge for

mental health care. One randomized controlled trial found that cognitive therapy for low-functioning

patients reduced avolition and improved functioning, using an average of 50.5 treatment sessions over

the course of 18 months. The aim of our current pilot study was to evaluate whether 20 sessions of

Cognitive Behavioral Therapy for negative symptoms (CBT-n) would reduce negative symptoms within 6

months. Also, we wanted to test the cognitive model of negative symptoms by analyzing whether

a reduction in dysfunctional beliefs mediated the effects on negative symptoms.

Method: In an open trial 21 adult outpatients with a schizophrenia spectrum disorder with negative

symptoms received an average of 17.5 sessions of CBT-n. At baseline and end-of-treatment, we assessed

negative symptoms (PANSS) and dysfunctional beliefs about cognitive abilities, performance, emotional

experience, and social exclusion. Bootstrap analysis tested mediation.

Results:The dropout rate was 14% (three participants). Intention-to-treat analyses showed a within group

effect size of 1.26 on negative symptoms (t 6.16, j Sig 0.000). Bootstrap analysis showed that

dysfunctional beliefs partially mediated the change.Limitations:The uncontrolled design induced efcacy biases. Also, the sample was relatively small, and

there were no follow-up assessments.

Conclusions: CBT-n may be effective in reducing negative symptoms. Also, patients reported fewer

dysfunctional beliefs about their cognitive abilities, performance, emotional experience, and social

exclusion, and this reduction partially mediated the change in negative symptoms. The reductions were

clinically important. However, larger and controlled trials are needed.

2013 Elsevier Ltd. All rights reserved.

1. Introduction

1.1. Negative symptoms

Negative symptoms of psychotic disorders include avolition,affective attening, social withdrawal, anhedonia, and poverty of

speech. A review demonstrates that these symptoms are strong

predictors of poor long-term prognosis (Lang, Ksters, Lang, Becker,

& Jger, 2012). They are clearly associated with low levels of

functioning(r0.42),which is notthe case forpositivesymptoms

(Ventura, Hellemann, Thames, Koellner, & Nuechterlein, 2009).

Even though negative symptoms are often regarded as stable

aspects of psychotic disorders such as schizophrenia, not changing

much or otherwise worsening over time, there is recent evidencethat both at affect and social functioning show important changes

during the course of ten years after a rst psychotic episode,

slowly deteriorating or improving for different patient subgroups

(Evensen et al., 2012). This installs hope for change and targeted

interventions. However, the treatment of negative symptoms in

schizophrenia is still a major challenge for mental health care.

Second generation antipsychotic medications produce only mod-

erate effects on negative symptoms (Leucht, Arbter, Engel, Kissling,

& Davis, 2009), and an exacerbation of negative symptoms due to

antipsychotics has also been reported (Artaloytia et al., 2006). More

effective treatments are needed.

* Corresponding author. Tel.:31 (0) 6 815 99 505.

E-mail addresses: [email protected], [email protected] (A.B.P. Staring),

[email protected] (M.-A.B. ter Huurne), [email protected]

(M. van der Gaag).

Contents lists available at SciVerse ScienceDirect

Journal of Behavior Therapy andExperimental Psychiatry

j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c om / l o c a t e / j b t e p

0005-7916/$e see front matter 2013 Elsevier Ltd. All rights reserved.

http://dx.doi.org/10.1016/j.jbtep.2013.01.004

J. Behav. Ther. & Exp. Psychiat. 44 (2013) 30 0e306
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1.2. Cognitive Behavioral Therapy (CBT) for negative symptoms

In the US, a randomized controlled trial with 60 patients was

conducted to assess the efcacy of a program for low-functioning

patients with neurocognitive impairments and negative symp-

toms (Grant, Huh, Perivoliotis, Stolar, & Beck, 2012). The program

was based on recent evidence that defeatist performance attitudes

(e.g. if you cannotdo somethingwell, there is little point in doing it

at all) correlate with negative symptoms (Beck, Grant, Huh,

Perivoliotis, & Chang, 2011;Couture, Blanchard, & Bennett, 2011)

and partially mediate the relationship between neurocognitive

performance and negative symptoms (Grant & Beck, 2009). This

means that patients beliefs about their neurocognitive impair-

ments are important in determining the extent to which these

impairments lead to withdrawal and inactivity. Also, in three

studies, using experience sampling methods, there was no evi-

dence for a decit in the experience of pleasure in patients with

psychotic disorders e rather, there were strong negative expec-

tanciesof experiencing pleasure (low anticipatory pleasure: I will

not be able to enjoy this)(Gard, Kring, Gard, Horan, & Green, 2007;

Oorschot et al., 2011). These beliefs predicted low social activity

levels (Oorschot et al., 2011). Another study found that asocial be-

liefs (e.g. having close friends is not as important as most peoplesay) were predictive of low social functioning one year later, rather

than the other way around (Grant & Beck, 2010).

This body of research implicates that low expectations for

pleasure and performance may strongly affect negative symptoms.

Grant et al. (2012)used cognitive therapy (CT) to correct dysfunc-

tional beliefs about pleasure, cognitive abilities, performance and

social functioning. Techniques included goal-setting, behavioral

experiments, activity scheduling, and more. Several accommoda-

tions were used to work around neurocognitive impairments. The

CT-group received 18 months of individual treatment. CT was found

to be superior in reducing avolition/apathy and improving levels of

functioning. However, other negative symptoms did not improve

signicantly, such as affective attening, alogia, and anhedonia-

asociality. Also, the treatment duration was long: an average of50.5 sessions.

Another recent and large randomized controlled trial compared

a shorter version of CBT for negative symptoms (average 16.6 ses-

sions) with cognitive remediation in 198 patients (Klingberg et al.,

2011). Treatment consisted of case formulation based on a cognitive

model, goal setting, discussion of cognitive processes, homework

assignments, and role-play. Patients received two out of ve

available treatment modules that target negative symptoms. The

aim was to reduce generalized expectancy of failure (defeatist be-

liefs) and improve social cognitive skills like emotion detection and

expression. The CBT treatment, in comparison to the trial ofGrant

et al. (2012), had a greater focus on training of cognition and

behavior, and a somewhat smaller focus on cognitive therapy for

dysfunctional beliefs. Results showed moderate improvements innegative symptoms in both groups, but no signicant benet for

CBT.

Although other studies of psychosocial interventions have been

conducted, they rarely targeted negative symptoms as their pri-

mary outcome. There have been three small but promising trials on

peer support groups (Castelein et al., 2008), music therapy (Gold,

Solli, Krger, & Lie, 2009), and body-oriented psychosocial ther-

apy (Rhricht & Priebe, 2006). Also, CBT for the positive symptoms

of psychotic disorders has been found to decrease negative symp-

toms: an average effect size of 0.44 (Wykes, Steel, Everitt, & Tarrier,

2008). Less paranoia and less fear for distressing voices may lead to

less withdrawal and more experience of pleasure. This illustrates

the well known multifactorial nature of negative symptoms: posi-

tive symptoms, anxiety, depression, and other symptom clusters

may exacerbate negative symptoms. Interventions that target those

factors therefore exert some effect on the negative symptoms as

well. For example, antidepressant medications are known to

decrease negative symptoms in schizophrenia (Singh, Singh, Kar, &

Chan, 2010). However, treatment of the more primary negative

symptoms remains a major challenge (Buckley & Stahl, 2007;

Kirkpatrick, Fenton, Carpenter, & Marder, 2006). Antipsychotics and

family interventions are unsatisfactory in this regard (Mkinen,

Miettunen, Isohanni, & Koponen, 2008). The trial of Grant et al.

(2012)is one of the most promising. More research is needed to

conrm to what extent specic CBT for negative symptoms may

reduce these symptoms as well as dysfunctional beliefs, and to

evaluate whether it can be achieved in fewer sessions than 50.

1.3. Aims of the study

Based on recent literature, we constructed a Dutch treatment

manual of Cognitive Behavioral Therapy for negative symptoms

(CBT-n) (Staring & Van den Berg, 2010; Staring & Van der Gaag,

2010). The aim of this uncontrolled pilot study was to test: (a)

whether the treatment manual is useful for therapists; (b) whether

CBT-n may be effective in reducing negative symptoms for patients

with a schizophrenia spectrum disorder, using a maximum of 20treatment sessions in six months; and (c) whether a reduction in

dysfunctional beliefs mediates the effect on negative symptoms.

Findings within this pilot study will be used as preparation for

a large RCT.

2. Materials and methods

2.1. Study design

An open pilot trial in which negative symptoms were treated

with CBT-n in participants with a schizophrenia spectrum disorder,

with a maximum of 20 treatment sessions.

2.2. Setting

Participants were outpatients from nine psychiatric institutions

in The Netherlands: Altrecht Psychiatric Institute, Mediant Psychi-

atric Institute, Parnassia Psychiatric Institute, Mental Health Care

Drenthe, Mental Health Care Breburg, Mental Health Care Noord-

Holland Noord, Rivierduinen Psychiatric Institute, GGNet, and

Reinier van Arkel Group.

2.3. Participants

Inclusion criteria were:

1. A chart diagnosis of schizophrenia spectrum disorder;

2. At least some negative symptoms (at least three PANSS neg-ative symptom items scoring a 3 or higher, bringing the total

score of the PANSS negative syndrome to at least 13) about

which the patient expressed dissatisfaction.

Exclusion criteria were:

1. Younger than eighteen years of age;

2. No mastery of the Dutch language;

3. Negative symptoms as a consequence of positive symptoms

(e.g. withdrawal due to paranoid delusions). This was assessed

within the initial information session by the therapist. He/she

asked the patient about the reasons for social withdrawal, low

activity levels, low pleasure experience levels, etc., and explic-

itly asked whether voices or certain psychotic fears play a role

A.B.P. Staring et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 300e306 301


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or not. Positive symptoms as such were not an exclusion cri-

terion; only when they were considered to be theprimary cause

of the negative symptoms, in which case CBT-p or another type

of intervention for positive symptoms was called for.

2.4. Procedure

After referral to this study, information was given verbally as

well as in writing, and written informed consent was obtained.

After that, baseline measurements were administered (T0). Par-

ticipants were then treated with weekly sessions of 45 min ac-

cording to the CBT-n manual, with a maximum of 20 sessions.

Treatment as usual (e.g. case management) was also continued.

Therapists worked in the same team as the case managers and kept

in touch about progress. Measurements were administered again at

the end-of-treatment (T1). In total, thirteen therapists participated

in the study. All therapists were health and clinical psychologists

with experience in CBT for psychosis. Ten had at least a two-year

post-doctoral clinical specialization. The therapists received

a one-day training in the CBT-n manual. Treatment integrity mea-

surements were not collected. The rst author did keep in touch

with all therapists about progress and gave consultation for the

various phases of the treatment for each participant.The Medical Ethics Committee of the University Medical Center

of Utrecht approved the study protocol (METC-protocol number:

11-228/C, date 10-06-2011).

2.5. Cognitive Behavioral Therapy for negative symptoms (CBT-n)

The treatment manual was based on the work of Grant and col-

leagues (Grant et al., 2012;Perivoliotis & Cather, 2009), but adapted

here and there, e.g. in order to make distinctions between various

dysfunctionalbeliefs and to furthert themodel with insights about

self-stigma, perceived discrimination and social exclusion, mourn-

ing over experienced losses, and states of demoralization. This is

basedon some recent literature. For example,in a recentstudy using

time budget to concisely measure activity levels, perceived dis-

crimination, within a measure of stigma appraisals, was found to be

associatedwith reducedactivity(Moriarty, Jolley,Callanan,& Garety,

2012). Patientswith psychosise possiblyas a consequenceof insight

into neurocognitive impairments and of the experienced losses due

to psychotic episodes and hospital admissions e may be vulnerable

for internalizing some highly stigmatizing beliefs about their illness

and for sliding into a state of demoralization. Indeed, assessing 145

outpatients, it was found that high insight combined with high self-

stigma predicted levels of demoralization in patients with psychotic

disorders (Cavelti, Kvrgic, Beck, Rsch, & Vauth, 2011). This is in line

with other studies that have found that a combination of good

insight together with stigmatizing illness appraisals renders a pa-

tient at risk forhigh levels of hopelessness as well as low self-esteem

and low quality of life (Lysaker, Roe, & Yanos, 2007;Staring, Van der

Gaag, Van den Berge, Duivenvoorden, & Mulder, 2009). Based on

this, as well as on theworkof Grantet al., we constructed a cognitive

model of negative symptoms (Fig.1).

The treatment manual started with a structured interview in

order to make an individual case formulation based on the model in

Fig. 1. A patients individual goals were assessed, and psycho-

education about neurocognitive impairments and dysfunctionalattitudes was provided. General activity scheduling and registra-

tions were applied, and signicant others were informed about the

treatment rationale. When the rst treatment goal had been cho-

sen, the case formulation provided insight into possible obstacles.

Dysfunctional beliefs and avoidance behaviors that stood in the

way of the goal constituted the targets of CBT-techniques, e.g.

cognitive restructuring and roleplay. Behavioral experiments and

other cognitive methods took place within the treatment sessions

as much as possible. Typical dysfunctional beliefs that were tar-

geted included: I got damaged by my psychotic episode and I cannot

enjoy things anymore, I have no energy at all and when I start

working again, even for a few hours, I will get a psychotic breakdown,

Negative self-image,self-stigmatization,expectation of social

exclusion

Reduced

emotional

competencies

Reduced

Reduced

behavioral

competencies

cognitive

competencies

Setbacks,

internal and

external loss-

experiences

(e.g. identity,

capacities,

education,

work,

relationships)

Negative expectations

about cognitive capacities, e.g. memory,

concentration, energy levels


about agency, performance and

social skills


about the ability to enjoy and

experience positive emotions

Primary interpretation:Impairment:

Secondary

interpretation: Avoidance:

Withdrawal, less expression,inactivity, defeatist attitude,

thought and emotion suppression

Psychoses

Fig. 1. Cognitive model of negative symptoms (Staring & Van der Gaag, 2010). On the left side, impairments are included that may be present in a psychotic disorder and that are

considered unchangeable using CBT. The psychotic episodes, setbacks, and experienced losses are summarized in the upper mid section of the gure; they have taken place in the

past and constitute no target for change. The current problems are summarized in the right and lower sides of the model. These are dysfunctional beliefs that are often characterized

by all-or-nothing polarization as well as by a connection with avoidance behavior.

A.B.P. Staring et al. / J. Behav. Ther. & Exp. Psychiat. 44 (2013) 300e306302


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or I am unable to concentrate and memorize anything new, and

therefore unable to study again. Visual aids, text-messages, imagery,

and the help of signicant others were used to work around neu-

rocognitive impairments. In order to promote a sense of personal

efcacy as much as possible, each failure of the patient to execute

a new behavior was interpreted to be the therapists fault by

insufcient preparation or setting the goals too high. They

responded with sentences like: This is myfault, I did not prepare you

enough for this step. Therapists were instructed to repeatedly get

this message across, as authentically as they were able to. The idea

is that small successes are highly needed for the patient to expe-

rience a sense of hope and personal efcacy. Little failures are

threats that patients may interpret as evidence for negative beliefs

about performance. Patients do not learn from failure and perform

better after errorless learning (Pope & Kern, 2006). However,

therapists were always careful to not install unrealistic beliefs or

goals. Finally, several techniques were used to keep the patient

attending the sessions, e.g. watching entertaining youtube-movies

during the rst part of the session.

2.6. Measurements

2.6.1. Primary outcomeThe negative syndrome of the Positive And Negative Syndrome

Scale (PANSS) (Kay, Fiszbein, & Opler, 1987) was used to assess

negative symptoms. It consists of 7 items and produces a total score

ranging from 7 (minimum) to 49 (maximum).

2.6.2. Mediator: dysfunctional beliefs

We intended to measure typical dysfunctional beliefs that con-

stitute the targets of CBT-n, in order to assess whether these would

mediate an effect on negative symptoms. However, no existing scale

ts these beliefs accurately. Although the Dysfunctional Attitudes

Scale e Defeatist Performance Attitude (DAS-DPA) (Weissman,

1978) correlated with negative symptoms in the aforementioned

studies, many of its items reect other attitudes than the perfor-

mance expectancies that constitute the beliefs in the model ofFig.1,and some of the beliefs we wanted to measure (e.g. low expec-

tancies about pleasure, energy or concentration) arenot included in

this scale. We therefore selected specic items from a range of

existing scales that seemed useful: the Beck Depression Inventory

secondedition (BDI-2) (Beck, Steer, Ball, & Ranieri,1996; Beck, Steer,

& Brown, 1996;Beck, Steer, & Garbin, 1988), the Beck Hopelessness

Scale (BHS) (Beck, Weissman, Lester, & Trexler, 1974), the Dysfunc-

tional Attitudes Scale e Defeatist Performance Attitude (DAS-DPA)

(Weissman, 1978), and the Internalized Stigma of Mental Illness

(ISMI) scale (Ritsher, Otilingam, & Grajales, 2003).

Reasoning from the model in Fig. 1, the selected items should

reect dysfunctional beliefs about cognitive abilities, (social) per-

formance, and the ability to experience positive emotions. Also, we

planned to measure beliefs about social exclusion and internalizedstigma.

(1) Dysfunctional beliefs about cognitive abilities: BDI-13 (indici-

siveness), BDI-15 (subjective loss of energy), BDI-19 (subjective

concentration difculty), and BDI-20 (experienced tiredness or

fatigue).

(2) Dysfunctional beliefs about (social) performance: BHS-2 (I

might as well give up because theres nothing I can do to

make things better for myself), BHS-6 inverted (In the future

I expect to succeed in what concerns me most ), DAS-DPA-6

(If I fail at my work, then I am a failure as a person ), DAS-

DPA-14 (If I ask a question, it makes me look inferior),

DAS-DPA-15 (I cannot trust other people because they might

be cruel to me

).

(3) Dysfunctional beliefs about experiencing pleasure and positive

emotions: BDI-4 (subjective loss of pleasure), BDI-10 (crying too

much or cannot cry), BDI-12 (loss of interest), BDI-21 (loss of

interest in sex), BHS-17 (It is very unlikely that I will get any

real satisfaction in the future).

Based on standardized item-scores (to equal their weights),

these 14 items were summed to constitute a score that reects the

primary beliefs in the model of Fig. 1. Cronbachs alpha of this

measure was 0.719, indicating an acceptable internal consistency.

(4) Beliefs about social exclusion and internalized stigma: ISMI

total score.

The ISMI contains 29 items rated on a four-point Likert-type

scale, ranging from 1 (strongly agree) to 4 (strongly disagree).

It contains ve subscales: alienation, stereotype endorsement,

perceived discrimination, social withdrawal, and stigma resist-

ance. For this study, ISMI total scores were used, in which higher

scores indicate more internalized stigma as well as more expe-

rienced or expected social exclusion. The measure has high

internal consistency and testeretest reliability. Construct and

concurrent validity were supported by comparisons with othermeasures.

The ISMI total score as well as the sum of the selected 14 items

were both standardized (transformed into z-scores). These two

scales were then added up to constitute a total measure of the

dysfunctional beliefs that were the main target of CBT-n. Higher

scores indicated more dysfunctional beliefs, with an average score

of zero at baseline.

2.7. Statistical analyses

Descriptive statistics were produced to describe the de-

mographic characteristics and baseline variables of the total

sample. Paired samples t-tests for means were performed to

determine the statistical signicance of the changes in scores onthe primaryoutcome as well as the mediating measure. Effect sizes

were used as indicators of clinical relevance of the observed

changes (Cohen, 1992). We also performed a regression-analysis,

in which it was checked whether a change in negative symptoms

would still be signicant when depression scores were controlled

for.

Deeper understanding is gained when we comprehend the

process that causes the effect. A variable is a mediating variable if

it (to a certain extent) accounts for the association between the

therapy and symptom reduction. Perfect or complete mediation

refers to an absence of treatment effect when the mediator has

been controlled for. When the treatment effect is reduced by

a non-trivial amount, but not to zero, partial mediation has

occurred (Baron & Kenny, 1986). To demonstrate mediation, thecausal steps strategy should be applied (Fig. 2). This means that

several results must be ascertained: (1) an effect of treatment on

BA M

C'Y

CYX

X

Fig. 2. Path models of the total effect of treatment on symptoms (uppergure) and

mediated effects of treatment on symptoms (lower gure). C is the total effect of

treatment X on symptoms Y. C0 is the direct effect of treatment X on symptoms Y with

the effects of mediator M partialled out. A is the effect of treatment X on mediator M

and B is the effect of mediator M on symptoms Y.



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symptoms (C path); (2) an effect of treatment on the mediator (A

path); (3) an effect of the mediator on symptoms (B path); and (4)

the effect of treatment on symptoms without the indirect effect of

the moderator must be non-trivially reduced or absent (C0 path).

In order to analyze whether dysfunctional beliefs mediated the

treatment effects on negative symptoms, we used the bootstrap

method that can handle non-parametric data and relatively small

sample sizes (Preacher & Hayes, 2008). The algorithm and syntax

for SPSS 18 are available on the Internet (Hayes, 2011). In our

uncontrolled design, however, all changes and mediations must

be interpreted with caution, as time effects are not necessarily due

to the treatment.

3. Results

3.1. Participants

A total of 34 patients, who met the criteria of the study, were

asked to participate. Eight refused. The remaining 26 patients

wanted to participate, but two did not enroll because of a physical

illness that required hospital treatment, two missed out on the

participation deadline, and one patient started another exper-

imental treatment. Twenty-one patients enrolled in the study, and

they constitute the participants sample for the intention-to-treat

analyses.

Three patients prematurely stopped treatment. Two of them

stopped halfway due to low motivation. Another patient got too

depressed to continue. All three were available for T1-measurements

and so we had no missing data for the intention-to-treat analyses.

Eighteen patients completed the treatment (Table 1).

3.2. Treatment execution

On average 17.5 sessions of CBT-n were provided to each

participant. Although most patients seemed to benet from the

therapy, the pace of progress varied considerably. Some therapists

noted that, when they continued the treatment program after theend-of-treatment measurement (T1) and beyond the maximum

of 20 sessions, patients would continue to benet in terms of

improved functioning and fewer negative symptoms. It thus seems

that some patients may accomplish more treatment gains if CBT-n

would be extended. Therapists also described that change in beliefs

and attitudes would come rst, followed by successful behavioral

activation.

In two cases, delusions turned out to be an obstacle for the

patient to engage in desired activities. Their positive symptoms

stood in the way of escaping withdrawal. One patient reported the

fear e after working with this goal for various sessions e that if he

would start socializing, his mother would read his thoughts and

disapprove. And one patient was afraid to return to horse riding,

because they might still be out to get him. Despite the exclusion

criterion of positive symptoms causing withdrawal, we had been

unable to see this beforehand. These patients were kept in treat-

ment and CBT-techniques were used to work on the positive

symptoms. After doing so, at least one of them was able to engage

in more constructive activity.

Therapists generally found that the treatment manual was clear

and concise. However, some therapists were struggling with the

distinction between actual neurocognitive impairments and the

patients beliefs about these impairments. Behavioral experiments

for testing beliefs in goal-specic situations (e.g. I want to study

this book for college, but my memory does not work ), rather thanusing neurocognitive test-batteries, often proved satisfactory in

solving this issue.

3.3. Outcome

The pre- to posttreatment results are shown in Table 2. The

improvement on the primary outcome measure was highly signif-

icant and clinically relevant. The effect size and PANSS-scores

indicate an important reduction of negative symptoms during the

course of treatment.

In order to control for depression, we performed a stepwise

regression-analysis to predict negative symptom levels, in which

we rst entered depression (BDI-2) as the independent variable,

and time point (either baseline or end of treatment) in the secondblock. This analysis showed that the change in negative symptoms

was not explained by a change in depression scores, as the effects of

depression in the regression analysis were non-signicant (t 1.07

j p 0.291) and the changes achieved during the treatment period

remained signicant (t 2.96 j p 0.005).

3.4. Mediation of dysfunctional beliefs

Specic results of the mediation analysis are presented in

Table 3. The total mediator model was signicantF(2, 39) 11.838,

p 0.0001. The total explained variance (R2) was 38%. The adjusted

R2 was 35%. Dysfunctional beliefs fullled the criteria for partial

mediation: therapy signicantly affected the mediator (path A), the

mediator signicantly affected negative symptoms (B), the directeffect of therapy on negative symptoms reduced when corrected

for dysfunctional beliefs (path C0 is less strong than path C), and the

bootstrap indirect effects were signicant. In short, the reduction of

dysfunctional beliefs partially mediated the reduction in negative

symptoms, although not completely.

4. Discussion

4.1. Outcome

The dropout rate was 14% (three out of twenty-one patients),

indicating that CBT for negative symptoms was an acceptable

treatment for these patients. This dropout rate is similar to other

psychosocial interventions for psychotic disorders (Villeneuve,

Table 1

Demographic characteristics of participants.

Frequency (n 21)

Mean age 40.6 years (range 22e58)

Sex Male 14

Female 7

Living status Alone, independently 19

In sheltered living 1

With parents 1

Ethnicity Dutch (western) 17

Non-western Immigrant 4

Psychotic disorder Schizophrenia 17

Schizoaffective disorder 1

Schizophreniform disorder 1

Psychotic disorder NOS 2

Mean duration of

psychotic disorder

13.0 years (range 1e26)

Substance abuse Alcohol abuse 4

Medic atio n Fi rst g ener ati on an ti psy cho ti c 7

Second generation antipsychotic 14



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Potvin, Lesage, & Nicole, 2010). This is positive in our view, given

the likelihood that patients with negative symptoms may be dif-

cult to motivate to fully complete their treatments.

A large within-group effect size was found on the PANSS

negative syndrome, changing from an average of 20.2 to 14.1,

indicating that CBT-n ts its purpose: to decrease negative

symptoms. The changes were clinically important and may surpass

the effects of other treatment methods for negative symptoms.

The Klinberg et al. (2011) study, for example, found the PANSS

negative syndrome score only changing from an average of 18.9 to

16.1 (in their article they mention the average item-scores of 2.7

and 2.3). And the controlled trial on body-oriented psychosocial

therapy (Rhricht & Priebe, 2006) found the PANSS negative syn-

drome changing from an average of 23.4 to 18.2. To conrm the

effectiveness of CBT-n, however, larger and controlled trials areneeded.

Also, we found a large effect size on our measure of dysfunc-

tional beliefs, which indicates that CBT-n may effectively target the

beliefs of our cognitive model. Furthermore, a reduction in these

beliefs partially mediated the change in negative symptoms. This

nding is evidence for their clinical importance and it supports our

cognitive model of negative symptoms. The mechanism of change

in negative symptoms is in part explained by the reduction

of dysfunctional beliefs. Also, however, a signicant part of the

change in negative symptoms was unexplained by dysfunctional

beliefs. This part of the effect may for example be more associated

with the goal-setting and behavioral activation components of the

treatment.

Patients appraised their illnesses in a less stigmatizing way andbecame more hopeful for the future. Besides relevant as a mecha-

nism for reducing negative symptoms, this improvement is also

important in itself. Other studies on psychosocial interventions that

target self-stigma, for example, have mostly produced small to

medium effects (Mittal, Sullivan, Chekuri, Allee, & Corrigan, 2012).

4.2. CBT-n manual

Based on the ndings we learned that although 20 treatment

sessions may accomplish important improvements for most pa-

tients, the therapy should probably be allowed to extend its dura-

tion when needed.

It was difcult to exclude patients that experience negative

symptoms as a consequence of delusions. Wemay sometimes fail todetect positive symptoms up until the time that a patient is actively

engaged to achieve goals. It is desirable that CBT-techniques for

positive symptoms are available when needed.

4.3. Limitations

This was an uncontrolled study. Therefore the efcacy ndings

are biased. Patients may have improved over the course of the

study by self-initiated change or because other treatments were

helpful. The lack of a control group means that this effect was not

controlled for.

Second, also as a consequence of the uncontrolled design,

measurements were not blind. We mostly used self-report mea-

surements, and patients were fully aware that they had received an

active treatment for their negative symptoms. This may have

caused efcacy to be overestimated.

Third, about 25% of the patients that we initially asked to par-

ticipate refused. Some of them did not want to participate in a sci-

entic project, whereas others seemed unwilling to work on theirnegative symptoms. This is a problem, as the negative symptoms

themselves may in part be the cause of these patients refusing

participation. Although we used various strategies to facilitate

participation, we were unable to engage 25% of the patients at the

start.

Fourth, we did not formally measure treatment integrity.

The therapists did ll in a form every therapy session, and

the rst author monitored the therapists adherence to the

manual.

Finally, there was no follow-up assessment, making it impos-

sible to determine whether treatment gain was maintained over

time.

Randomizedcontrolled trials with sufcient statistical power

will need to be performed in order to conrm or refute our results.

4.4. Conclusions

CBT-n seemed effective in reducing negative symptoms. The

changes were partially explained by a reduction in dysfunctional

beliefs about cognitive abilities, performance, emotional experi-

ence, self-stigma, and social exclusion. The changes were clinically

important.

Limitations of this study include the uncontrolled design. Ef-

cacy was probably overestimated. Also, the patient sample was

relatively small, and we performed no follow-up measurements.

Larger and better designed trials are needed.

Declaration of interest

None. No special funding was used and no conicts of interest

exist with regard to this study.

Table 3

Results of mediation analysis on negative symptoms (PANSS) with bootstrapping.

Direct and total effects p-values Bootstrap indirect effects 95% condence interval (A*B path)

A B C(0) Lower limit Upper limit

Total treatment effect (without mediation) 0.000 (C)

Dysfunctional beliefs as mediator 0.004 0.028 0.007 (C0) 0.285 3.669

C, total effect of treatment (time) on negative symptoms; A, effect of treatment on the mediator dysfunctional beliefs; B, effect of dysfunctional beliefs on negative symptoms;

C0 effect of treatment on negative symptoms without the indirect effect of the mediator dysfunctional beliefs; A*B path, bootstrap results for the indirect effect; lower and

upper limits of con

dence interval for test of mediation with 5.000 bootstrap re-samples and bias correction.

Table 2

Paired samplest-test statistics for the mean changes between baseline and end-of-treatment. Intention-to-treat analysis (n 21).

Baseline mean (sd) End-of-treatment mean (sd) t(2-tailed) p Effect size Cohensd

PANSS negative syndrome 20.2 (4.3) 14.1 (5.3) 6.16 0.000 1.26

Dysf unctional beliefs 0.00 (1.68) 1.51 (1.50) 3.84 0.001 0.95

PANSS: positive and negative syndrome scales.



7/7

Acknowledgments

We would like to acknowledge the contributions by the thera-

pists of this study: Rob van Grunsven, Chris van Oeveren, Kwok

Wong (Altrecht Psychiatric Institute), Anouk Nienhuis, Mary-Ann

ter Huurne, Peter van Veen (Mediant Psychiatric Institute), Clau-

dia Berwers (Parnassia Psychiatric Institute), Roxanne Valk (Mental

Health Care Drenthe), Marije Quadackers (Mental Health Care

Breburg), Heleen Begheijn (Mental Health Care NoordHolland

Noord), Matty Geurink (Rivierduinen Psychiatric Institute), Fabian

Shug (GGNet), and Bas van Oosterhout (Reinier van Arkel Group).

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