An interventional study of CHAMPS and I Can Change in First Episode Psychosis (FEP), Psychosis and Schizophreni-form Disorder, sponsored by Centre hospitalier de l'Université de Montréal (CHUM). Not yet recruiting. Open to participants aged 18 Years to 35 Years. Per ClinicalTrials.gov, last updated 2026-09-10.
Sponsored by Centre hospitalier de l'Université de Montréal (CHUM) · Not applicable, Interventional, and Supportive care
Psychotic disorders affect approximately 4% of Canadians and have a significant impact on individuals' well-being, their families and social networks, and healthcare systems. The development of psychosis is explained by a complex interplay of genetic and environmental factors, including the use of psychoactive substances. Frequent cannabis use can contribute to the development of psychotic disorders.
The prevalence of cannabis use disorder (CUD) in individuals with a first-episode psychosis (FEP) followed in Early Intervention Services (EIS) is 42-53%, well above that of the general population (\~3%). Cannabis use in individuals with psychosis is associated with increased symptom severity, higher rates of relapse and hospitalization, and poor psychosocial functioning.
Standardized mobile app-based interventions offer a scalable and accessible solution. Our team developed and piloted CHAMPS (harm reduction) and iCanChange (use reduction/cessation) with favourable results: retention 82% (CHAMPS) and 84-86% (iCC), high satisfaction, and preliminary efficacy signals. The two pilot studies were targeting feasibility, this study is studying efficacy of the two app-based interventions (CHAMPS and iCanChange).
1,587 studies on the registry are indexed under Psychotic Disorders; 281 are open to participants now.
This study's planned enrollment of 550 is above the median of 65 across 1,320 interventional studies indexed under Psychotic Disorders.
Browse Psychotic Disorders studies →Centre hospitalier de l'Université de Montréal (CHUM) is the lead sponsor of 376 studies on the registry; 110 are open to participants now.
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CHAMPS INTERVENTION
I CAN CHANGE INTERVENTION
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
DSM diagnostic criteria
The American Psychiatric Association’s manual of mental health diagnoses. DSM-5 (2013, revised as DSM-5-TR in 2022) replaced DSM-IV, and some studies still name the older edition. “Meets DSM criteria for …” means diagnosed by that edition’s diagnostic criteria, usually by a clinician in an interview.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants who receive the CHAMPS intervention
Other: CHAMPS
Participants who are not receiving the CHAMPS intervention and are compared to the one who do
Participants who receive the I Can Change intervention
Other: I Can Change
Participants who are not receiving the I Can Change intervention and are compared to the one who do
CHAMPS is a psychosocial e-intervention grounded in motivational interviewing (MI) and harm reduction principles, developed using the Behavioral Change Wheel (BCW) theoretical framework. CHAMPS is delivered through a mobile health platform and comprises 6 sequential psychotherapeutic modules (5-15 minutes each) plus a booster session: Module 1: Automatic personalized feedback on current cannabis PBS based on baseline assessment, with improvement suggestions and identification of strengths that facilitate change. Module 2: Exploration of personal values and the potential benefits of safer cannabis use practices Module 3: Evidence-based cannabis PBS using interactive psychoeducational techniques Module 4: Goal-setting using the SMART technique; participants define their own realistic cannabis-focused goals Module 5: Review of goal progress; support to revise current goal or adopt new consumption habits Module 6: Reassessment of consumption habits (PBS)
iCanChange (iCC) is a mobile app-based psychological intervention that incorporates principles of CBT, MI, and psychoeducation. It is available on Android and iPhone, in both English and French. Section 1 (10 modules): Modules 1 to 9 address topics such as cannabis dependence, myths, and its effects on psychosis, while helping users identify personal triggers, strengths, and benefits of reducing use. Section 1 concludes with Module 10, in which participants self-identify a flexible, person-oriented cannabis use goal such as reducing or stopping use. Two weeks after Module 10, an additional module is offered (up to two times) to consolidate and review goals. Section 2 (8 modules): Modules aim at increasing coping skills, equipping users with practical tools to maintain progress, planning cannabis-free activities, building social support, managing stress, and adopting a healthy lifestyle. Booster modules (3 sessions, one per month during the 12-week follow-up)
CHAMPS Primary Outcome Measure
To determine whether adding CHAMPS (an intervention aimed at developing safer consumption behaviors) to standard EIS is superior to standard EIS alone in reducing cannabis-related problems in young adults with FEP who are not seeking to cease or reduce their use. Total score of the Marijuana Problems Scale (MPS, 19 items, 0-38) at Week 8 post-randomization (also assessed at Week 12 post-randomization). Minimum clinically important difference (MCID): 2 points. For each MPS item, the participant rates a cannabis-related problem over the past month on a three-point scale: 0 = not a problem, 1 = a minor problem, 2 = a serious problem. Total scores range from 0 to 38; higher scores indicate more serious problems.
Time frame: Week 8 post randomization
I Can Change Primary Outcome Measure
To determine whether adding iCC to standard services offered in EIS clinics is superior to standard EIS alone in reducing the frequency of cannabis use in individuals with FEP and CUD (moderate to severe) who are seeking to reduce or cease their use. Number of days of cannabis use in the past 14 days (Timeline Follow Back, TLFB) at Week 12 (also assessed at Weeks 6 and 24 post-randomization).
Time frame: Week 12 post randomization
CHAMPS secondary Outcome Measure
Number of days of cannabis use in the past 14 days - Timeline Follow Back (TFLB) The TLFB will assess self-reported days of cannabis use over the past 14 days , as well as type of cannabis products, provenance, form, and quantity . The main endpoint for this outcome is the number of days per week of cannabis use. Days per week is the preferred manner of reporting cannabis use frequency in the field, and use of cannabis once per week or more is an established threshold for increased risk of adverse psychosis-related outcomes.
Time frame: week 0-8-12
CHAMPS secondary Outcome Measure
Protective behavioral strategies: PBSM total score (17 items, 15-73) The PBSM is a 17-item, self-report measure including various evidence-based strategies that cannabis users can adopt to reduce harms or use more safely. For each item, participants rate the degree to which they engage in a specific protective behavior on a scale of 1 = Never to 6 = Always. Individual item responses are summed for a total score, which is then converted to an item-response theory scaled score (possible range: 15-73). Higher scaled scores indicate greater use of PBS.
Time frame: week 0-8-12
CHAMPS secondary Outcome Measure
The proportion of participants in each State of Change Designation (i.e., precontemplation, contemplation, and action) Readiness to change Questionnaire (RCQ) Motivation to change cannabis use practices will be assessed using the adapted 12-item Readiness-to-Change Questionnaire (RCQ), modified for cannabis use. The RCQ is based on Prochaska and DiClemente's stages-of-change model and assesses three stages: pre-contemplation, contemplation, and action. For each scale, 4 items are summed (range: -8 to +8); the scale with the highest score represents the participant's Stage of Change Designation. The internal consistency of the three subscales is acceptable. The tool is designed for cannabis users not seeking treatment who may be unaware of a problem.
Time frame: week 0-8-12
CHAMPS secondary Outcome Measure
Quality of life: WHOQOL-BREF (26 items, 4 domains, 0-100) Quality of life will be measured using the WHOQOL-BREF, which assesses four domains: physical health, psychological health, social relationships, and environment, plus two overall items. The WHOQOL-BREF consists of 26 items; each item is rated on a 5-point Likert scale ranging from very poor to very good. Domain scores are calculated according to WHOQOL-BREF guidelines and converted to a 0-100 scale; an overall total score will also be calculated .
Time frame: week 0-8-12
I Can Change Secondary Outcome Measure
Cannabis dependence severity will be assessed using the Severity of Dependence Scale (SDS), a 5-item self-report questionnaire validated in people with early psychosis. Items are scored 0-3; total scores range from 0-15 (higher = greater dependence severity).
Time frame: Week 0-6-12-24
I Can Change Secondary Outcome Measure
Motivation to reduce cannabis use will be assessed using the Precaution Adoption Process Model (PAPM), a theoretical stage-based model that classifies individuals into 6 nominal stages: (1) unaware, (2) unengaged, (3) undecided, (4) decided not to act, (5) decided to act, (6) acting. Stages will be dichotomized for inter-group comparison (e.g., pre-action vs. action stages).
Time frame: Week 0-6-12-24
I Can Change Secondary Outcome Measure
In addition to frequency (primary endpoint), the timeline follow back (TLFB) will capture continuous abstinence (proportion of participants with 0 days of cannabis use in past 14 days) and estimated quantity of cannabis used per session.
Time frame: Week 0-6-12-24
I Can Change Secondary Outcome Measure
Quality of life will be measured using the WHOQOL-BREF, which has been validated in individuals with psychotic disorders and consists of 26 items across 4 domains: physical health, psychological health, social relationships, and environment. Each item is rated on a 5-point Likert scale ranging from very poor to very good. For each domain, scores are calculated according to WHOQOL-BREF guidelines and converted to a 0-100 scale.
Time frame: Week 0-6-12-24
No study locations are listed for this record.
Plan to share: Undecided — Research personnel will inform participants that all information collected will remain strictly confidential to the extent prescribed by law, and that no individually identifiable information will be revealed in any publication or presentation. Only authorized persons having an authentication code and designated data access group have access to the REDCap databases. Protection, detection and correction measures are implemented to maintain data confidential. A potential breach of confidentiality, notably regarding substance use, could conceivably result in negative legal or social consequences.
This study is not yet recruiting, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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