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Psychotic DisordersEPICNCT05703698

EEG Outcomes From Cognitive Behavioural Therapy for Psychosis

A study testing Cognitive Behavioural Therapy for Psychosis in people with Psychotic Disorders and Schizophrenia and Related Disorders, run by University of Toronto at 1 site in Canada.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Despite overwhelming evidence for neurocognitive and neurophysiological factors involved in the etiology of psychosis, these factors have never been examined as mechanisms of improvement from CBTp. Read more about this study

Who is it for?
Ages 18 to 65 years
What is being tested?
Cognitive Behavioural Therapy for Psychosis
Could I receive a placebo?
No, everyone receives an active treatment
How many people
20 participants
Where
1 siteCanada
Study dates
1 Feb 2023to 13 Nov 2024
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 65 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • The inclusion criteria is anyone who meets the criteria of schizophrenia, schizoaffective disorder or any other psychotic disorder, are also 18-65 years of age, are not abusing drugs or alcohol and can read and speak English. Participants must be experiencing active symptoms of psychosis as indicated on the PANSS.

Who cannot join

  • Exclusion criteria include anyone with a neurological disease or neurological damage, medical illnesses that can change neurocognitive function, a medical history of head injury with loss of consciousness and those with physical handicaps that would prevent them from engaging in assessment procedures

Trial locations and contacts

1 site in 1 country.

Canada1 site

  • University of Toronto Scarborough

    Scarborough Village, Ontario, M1C 1A4

Other trials in Canada

About this study

Despite overwhelming evidence for neurocognitive and neurophysiological factors involved in the etiology of psychosis, these factors have never been examined as mechanisms of improvement from CBTp. The first aim in the present study is to examine neurophysiological outcomes from CBTp using electroencephalography (EEG). The second aim is to examine neurocognitive outcomes from CBTp. This is an open-label pilot study. Twenty participants will receive CBTp and will be assessed at baseline and after 4 months.

Read the detailed description

Despite decades of refining traditional treatments for schizophrenia-spectrum disorders, recovery rates remain unchanged at only 13.5%, and there is an urgent need for innovative new interventions. Cognitive behavioural therapy has more recently been applied to treating psychosis and initial evidence has suggested that cognitive behavioural therapy for psychosis (CBTp) is the most effective psychosocial intervention available for psychosis. However, the efficacy of CBTp has been limited to moderate effect sizes. Little is currently understood about the mechanisms of CBTp, and a greater understanding of mechanisms is necessary in order to improve treatment efficacy. Despite overwhelming evidence for neurocognitive and neurophysiological factors involved in the etiology of psychosis, these factors have never been examined as mechanisms of improvement from CBTp. Cognitive behavioural therapy for psychosis (CBTp) has demonstrated efficacy for reducing positive symptoms, negative symptoms, and improving community functioning6 for individuals diagnosed with psychotic disorders. Despite meta-analytic evidence for the efficacy of CBTp, little is known about the neurophysiological processes through which symptomatic and functional change occurs. Electroencephalography (EEG) provides temporally precise measurement of neurophysiological activity. Positive symptoms have been associated with reduced integration of discrepant information as indexed by the N400 event-related potential, reduced resting state power in the EEG alpha frequency band, and reduced cognitive control as indexed by EEG alpha and theta power during cognitive flanker tasks. Additionally, neurocognitive abilities such as attention, memory, and problem solving are the best predictors of community functioning among individuals diagnosed with psychotic disorders. Although CBTp improves community functioning,[6] neurophysiological and neurocognitive outcomes have never been examined as therapeutic mechanisms from CBTp, despite the fact that therapeutic processes would be expected to improve cognitive functions.

Aim 1: Examine neurophysiological outcomes from CBTp using EEG.

Aim 2: Examine neurocognitive outcomes from CBTp

Hypothesis 1: After CBTp it is expected that participants will have a) increased N400 amplitude; b) increased resting state EEG alpha power; and c) reduced alpha and increased theta power during a flanker task

Hypothesis 2: After CBTp participants will have increased global neurocognitive abilities as indexed by a neurocognitive composite score.

Although CBTp has demonstrated efficacy to improve symptoms for individuals experiencing psychosis, little is known about the neurophysiological process through which this improvement occurs, and neither EEG nor neurocognitive outcomes from CBTp have ever been examined. The current results will provide preliminary evidence for neurophysiological mechanisms of change from CBTp that will increase understanding of the disorder and provide critical insights for refining psychotherapeutic interventions. Additionally, psychotherapy trials typically only examine psychological outcomes, however, if CBTp is effective it would be expected that this could be detected at both the neurophysiological level and neurocognitive level as well. My incorporation of multiple levels of assessment in clinical trials was recently praised as a goldstandard approach to trial methodology. This line of research is critical to improving the efficacy of CBTp.

Being tested
Cognitive Behavioural Therapy for Psychosis
Keywords
Psychosis, Electroencephalogram, CBTp, CBT
Medical subject headings
Psychotic Disorders, Schizophrenia

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Cognitive Behavioural Therapy for PsychosisBehavioural

    Also called CBT, CBTp

    CBT will be delivered according to an established manual that the PI has previously used successfully for in-person treatment. Treatment will consist of individual sessions with a psychologist employed by the University of Toronto for 1-hour per week for 6-months, or by one of the listed clinical graduate students under his supervision. All treatment will be delivered in-person. This treatment will be delivered in addition to usual care and no changes to usual care will be required.

Study groups in NCT05703698
Study groupRoleWhat they receive
Cognitive Behavioural Therapy for psychosisExperimentalCBTp will be delivered according to an established manual that the PI has previously used successfully for in-person treatment. Treatment will consist of individual sessions with a psychologist employed by the University of Toronto for 1-hour per week for 6-months, or by one of the listed clinical graduate students under his supervision. All treatment will be delivered in-person. This treatment will be delivered in addition to usual care and no changes to usual care will be required.
Receives: Behavioral: Cognitive Behavioural Therapy for Psychosis

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Positive and Negative Syndrome Scale (PANSS) Total Score

    The PANSS is a 30-item semi-structured interview assessing positive, negative symptoms and general psychopathology. Each item is scored on a 7-point scale (1 = absent, 2 = minimal, 3 = mild, 4 = moderate, 5 = moderate severe, 6 = severe, 7 = extreme). The lowest score would be a 30 and the highest score would be 210. A higher score would indicate increased symptomology.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

Secondary outcomes (13)

  1. Personal and Social Performance Scale (PSP)

    The PSP assesses community functioning through a brief interview with the participant about their daily activities. It contains 4 areas: (1) socially useful activities; including work and study; (2) personal and social relationships; (3) self-care; (4) disturbing and aggressive behaviors. The total score ranges from 1 to 100 and is interpreted on a 10-point intervals. Lower scores indicates more severe functional impairment while higher scores indicate better functioning.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  2. The Psychotic Symptom Rating Scales (PSYRATS)

    The PSYRATS assesses frequency and distress associated with the experiences of auditory hallucinations and delusions based on the PANSS interview. Each of the 17 items is scored on a 5-point scale, where a score of 0 indicates no presence, and 4 indicates the highest severity. The lowest score would be a 0 and the highest score would be 68. A higher score would indicate increased symptomology.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  3. Calgary Depression Scale for Schizophrenia (CDSS)

    The CDSS is a 9-item interview-based measure of depression symptoms specifically designed for use with people experiencing schizophrenia. Each item is scored on a 4-point scale (0 = absent, 1 = mild, 2 = moderate, 4 = severe). The lowest score would be a 0 and the highest score would be 36. A higher score would indicate increased severity of depressive symptoms.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  4. The Questionnaire About the Process of Recovery (QPR)

    QPR is a self-report measure assessing recovery with people experiencing psychosis. This version contains 22 items while the response to each statement is scored on a 5-point Likert scale ranging from "0 = strongly disagree" to "4 = strongly agree". The lowest possible score is 0 and the highest score could be 88. Higher scores would indicate better recovery.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  5. Beliefs About Paranoia Scale (BAPS)

    The BAPS is a 31-item self-report measure assessing metacognitive beliefs about paranoia. The degree of agreement to each statement is scored on a 4-point scale (1 = not at all, 2 = somewhat, 3 = moderately so, 4 = very much). Scales include positive, negative and normalizing beliefs about paranoia, and paranoia as a survival strategy. The lowest score would be 31 and the highest score would be 124. Higher scores are indicative of more beliefs and are shown to be related to paranoid ideation.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  6. Beliefs About Voices Questionnaire (BAVQ)

    BAVQ-R is a 35-item self-report measure assessing metacognitive perception, feelings about and reaction to auditory hallucinations. The degree of agreement to each statement is scored on a 4-point scale, ranging from disagree to strongly agree. Five subscales (malevolence, benevolence, omnipotence, resistance, engagement) are included. The lowest possible score is 0 and the highest score would be 105. Higher scores would indicate a tighter relationship with voices.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  7. Experiences Questionnaire (EQ)

    The EQ is a 11-item self-report measure assessing observations of thoughts and self. Frequency of experiences is scored on a 5-point scale, ranging from "1 = never" to "5 = all the time". The lowest possible score is 11 while the highest score would be 55. Higher scores would indicate increased levels of self-acceptance and mindfulness.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  8. Brief Core Schema Scale (BCSS)

    The BCSS is a 24-item self-report measure assessing positive and negative judgments individuals hold about themselves and others. Responses are first given dichotomously as "no" or "yes". "No" is scored as 0 and if the answers are "yes", the intensity of beliefs are then rated on a 4-point scale (1 = believe it slightly, 2 = believe it moderately, 3 = believe it very much, 4 = believe it totally). The lowest score would be a 0 and the highest score would be a 96. Higher scores in the positive-self subscale indicate more positive beliefs about selves, while higher scores in the negative-self subscale indicate more negative beliefs about selves. Higher scores in the positive-others subscale indicate more positive beliefs about others, while higher scores in the negative-others subscale indicate more negative beliefs about others.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  9. Dysfunctional Attitude Scale (DAS)

    DAS is a 40-item self-report measure assessing dysfunctional beliefs. The degree of agreement to each statement is scored on a 7-point Likert scale (1 = agree totally, 2 = agree very much, 3 = agree slightly, 4 = neutral, 5 = disagree slightly, 6 = disagree very much, 7 = disagree totally). The lowest possible scale is 40 while the highest possible scale is 280. Higher scores would indicate more negative beliefs.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  10. Davos Assessment of Cognitive Biases Scale (DACOBS)

    DACOBS is a 42-item self-report inventory assessing cognitive processing biases associated with psychosis. The degree of agreement to each statement is scored on a 7-point Likert scale, ranging from "1 = strongly disagree" to "7 = strongly agree". The lowest score would be a 42 and the highest score would be a 294. Higher scores would indicate more cognitive biases.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  11. Childhood Trauma Questionnaire (CTQ)

    The CTQ is a 28-item self-report measure assessing experiences of trauma during childhood. Frequency of experiences is reported on a 5-point scale, ranging from "never true" to "very often true". Reverse-coded items are included. The lowest score would be a 28 and the highest score would be a 140. Higher scores would indicate more trauma exposure.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  12. Working Alliance Inventory (WAI)

    The WAI assesses the quality of the therapeutic relationship. 36 items are to be completed both by the therapist and the client. Frequency of experiences are rated on a 7-point Likert scale (1 = never, 2 = rarely, 3 = occasionally, 4 = sometimes, 5 = often, 6 = very often, 7 = always). Reverse-coded items are included. The lowest score would be a 36 and the highest score would be a 252. Highest scores would indicate more therapeutic alliance.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

  13. Psychological Distance Scaling Task (PDST)

    The PDST is an experimental task associated with cognitive processing biases in psychosis. It gives measure of both how positive and negative a person views themselves, and how tightly held these beliefs are based on the clustering of the ratings. Participants would place adjectives on the grid based on self-descriptiveness and valence, while responses ranging from "not at all like me" to "very much like me" and "very negative" to "very positive". Smaller interstimulus distances among negative self-relevant adjectives and greater interstimulus distances among positive self-relevant adjectives would indicate more negative biases about selves.

    Measured: Change from Baseline to Follow-up (6 months post treatment)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted30 Jan 2023
  2. Study start1 Feb 2023
  3. Primary completion13 Nov 2024
  4. Study completion13 Nov 2024

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Treatment
Allocation
Not applicable
Intervention model
Single group
Model description
Formulation-based CBTp will be delivered with a maximum of 30 sessions over 6 months based on an established manual.
Masking
None (open label)
Enrolment
20 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05703698
Sponsor's protocol ID
38831
Acronym
EPIC
Status last verified
Jul 2024
First submitted
19 Jan 2023
Last updated
29 Jul 2025
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
No

Publications

  • Jaaskelainen E, Juola P, Hirvonen N, McGrath JJ, Saha S, Isohanni M, Veijola J, Miettunen J. A systematic review and meta-analysis of recovery in schizophrenia. Schizophr Bull. 2013 Nov;39(6):1296-306. doi: 10.1093/schbul/sbs130. Epub 2012 Nov 20.

    PubMed 23172003

  • Alvarez-Jimenez M, Parker AG, Hetrick SE, McGorry PD, Gleeson JF. Preventing the second episode: a systematic review and meta-analysis of psychosocial and pharmacological trials in first-episode psychosis. Schizophr Bull. 2011 May;37(3):619-30. doi: 10.1093/schbul/sbp129. Epub 2009 Nov 9.

    PubMed 19900962

  • van der Gaag M, Valmaggia LR, Smit F. The effects of individually tailored formulation-based cognitive behavioural therapy in auditory hallucinations and delusions: a meta-analysis. Schizophr Res. 2014 Jun;156(1):30-7. doi: 10.1016/j.schres.2014.03.016. Epub 2014 Apr 14.

    PubMed 24731619

  • Morrison AP, Turkington D, Pyle M, Spencer H, Brabban A, Dunn G, Christodoulides T, Dudley R, Chapman N, Callcott P, Grace T, Lumley V, Drage L, Tully S, Irving K, Cummings A, Byrne R, Davies LM, Hutton P. Cognitive therapy for people with schizophrenia spectrum disorders not taking antipsychotic drugs: a single-blind randomised controlled trial. Lancet. 2014 Apr 19;383(9926):1395-403. doi: 10.1016/S0140-6736(13)62246-1. Epub 2014 Feb 6.

    PubMed 24508320

  • Grant PM, Huh GA, Perivoliotis D, Stolar NM, Beck AT. Randomized trial to evaluate the efficacy of cognitive therapy for low-functioning patients with schizophrenia. Arch Gen Psychiatry. 2012 Feb;69(2):121-7. doi: 10.1001/archgenpsychiatry.2011.129. Epub 2011 Oct 3.

    PubMed 21969420

  • Morrison AP, Law H, Carter L, Sellers R, Emsley R, Pyle M, French P, Shiers D, Yung AR, Murphy EK, Holden N, Steele A, Bowe SE, Palmier-Claus J, Brooks V, Byrne R, Davies L, Haddad PM. Antipsychotic drugs versus cognitive behavioural therapy versus a combination of both in people with psychosis: a randomised controlled pilot and feasibility study. Lancet Psychiatry. 2018 May;5(5):411-423. doi: 10.1016/S2215-0366(18)30096-8. Epub 2018 Apr 5.

    PubMed 29605187

  • Jackson F, Foti D, Kotov R, Perlman G, Mathalon DH, Proudfit GH. An incongruent reality: the N400 in relation to psychosis and recovery. Schizophr Res. 2014 Dec;160(1-3):208-15. doi: 10.1016/j.schres.2014.09.039. Epub 2014 Oct 22.

    PubMed 25449716

  • Bowie CR, Reichenberg A, Patterson TL, Heaton RK, Harvey PD. Determinants of real-world functional performance in schizophrenia subjects: correlations with cognition, functional capacity, and symptoms. Am J Psychiatry. 2006 Mar;163(3):418-25. doi: 10.1176/appi.ajp.163.3.418.

    PubMed 16513862

  • Kay SR, Fiszbein A, Opler LA. The positive and negative syndrome scale (PANSS) for schizophrenia. Schizophr Bull. 1987;13(2):261-76. doi: 10.1093/schbul/13.2.261.

    PubMed 3616518

  • Nuechterlein KH, Green MF, Kern RS, Baade LE, Barch DM, Cohen JD, Essock S, Fenton WS, Frese FJ 3rd, Gold JM, Goldberg T, Heaton RK, Keefe RS, Kraemer H, Mesholam-Gately R, Seidman LJ, Stover E, Weinberger DR, Young AS, Zalcman S, Marder SR. The MATRICS Consensus Cognitive Battery, part 1: test selection, reliability, and validity. Am J Psychiatry. 2008 Feb;165(2):203-13. doi: 10.1176/appi.ajp.2007.07010042. Epub 2008 Jan 2.

    PubMed 18172019

  • Vinogradov S. Has the Time Come for Cognitive Remediation in Schizophrenia...Again? Am J Psychiatry. 2019 Apr 1;176(4):262-264. doi: 10.1176/appi.ajp.2019.19020160. No abstract available.

    PubMed 30929502

  • Kim M, Lee TY, Lee S, Kim SN, Kwon JS. Auditory P300 as a predictor of short-term prognosis in subjects at clinical high risk for psychosis. Schizophr Res. 2015 Jul;165(2-3):138-44. doi: 10.1016/j.schres.2015.04.033. Epub 2015 May 5.

    PubMed 25956629

  • Scherbaum S, Fischer R, Dshemuchadse M, Goschke T. The dynamics of cognitive control: evidence for within-trial conflict adaptation from frequency-tagged EEG. Psychophysiology. 2011 May;48(5):591-600. doi: 10.1111/j.1469-8986.2010.01137.x. Epub 2010 Nov 2.

    PubMed 21044093

  • Morrison AP, French P, Walford L, Lewis SW, Kilcommons A, Green J, Parker S, Bentall RP. Cognitive therapy for the prevention of psychosis in people at ultra-high risk: randomised controlled trial. Br J Psychiatry. 2004 Oct;185:291-7. doi: 10.1192/bjp.185.4.291.

    PubMed 15458988

  • Blackburn, I., James, I., Milne, D., Baker, C., Standart, S., Garland, A., & Reichelt, F. The revised cognitive therapy scale (CTS-R): Psychometric properties. Behavioural and Cognitive Psychotherapy. 2001; 29(4): 431-446.

Questions about this trial

What is this clinical trial studying?

A study testing Cognitive Behavioural Therapy for Psychosis in people with Psychotic Disorders and Schizophrenia and Related Disorders, run by University of Toronto at 1 site in Canada.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 1 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 29 Jul 2025. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in Canada. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Positive and Negative Syndrome Scale (PANSS) Total Score (time frame: Change from Baseline to Follow-up (6 months post treatment)). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05703698, which also lists 15 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jul 2025.

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