CANreduce 3.0 - a web-based self-help program for reducing cannabis use that explores the effectiveness of mindfulness and cognitive behavioral therapy approaches

CANreduce 3.0 - Randomized controlled trial testing the effectiveness of two different versions (mindfulness and CBT) of an adherence-focused web-based self-help intervention to reduce cannabis use in frequent cannabis users

Status

Recruiting

Phases

Unknown

Study type

Interventional

Source

ISRCTN

Registry ID

ISRCTN14971662

Enrollment

630

Registered

2021-09-09

Start date

2021-09-13

Completion date

Unknown

Last updated

2023-01-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Frequent cannabis use Mental and Behavioural Disorders Mental and behavioural disorders due to use of cannabinoids

Interventions

Current interventions as of 24/01/2022: The three-arm randomized controlled trial aims to test the effectiveness of a newly developed integrated mindfulness-based minimally guided self

Arm 2) with a control condition (Arm 3) in 630 individuals with frequent cannabis use. Moreover, we will explore similarities between the main intervention (arm 1) and the reference product (arm 2) fo

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: Current inclusion criteria as of 24/01/2022: 1. Cannabis use of at least once a week 30 days prior to study entry 2. At least 18 years old 3. At least weekly internet access and a valid email address and phone number 4. Informed consent (via a web form) Previous inclusion criteria: 1. Cannabis use of at least once a week 30 days prior to study entry 2. At least 18 years old 3. At least weekly internet access and a valid email address

Exclusion criteria

Exclusion criteria: 1. Current pharmacological psychiatric disease or history of psychosis, schizophrenia, bipolar type I disorder or significant current suicidal thoughts 2. Use of other pharmacological and psycho-social treatments for cannabis use disorders 3. Inability to read or write in German

Design outcomes

Primary

Measure	Time frame
Number of days of cannabis use in the last 30 days measured using self-report at baseline, after 6 weeks, and at 3 and 6 months follow-up.	—

Secondary

Measure	Time frame
Current secondary outcome measures as of 24/01/2022: 1. Cannabis use frequency and amount over the past 7 days according to the "time-line-follow-back" (TLFB) method 2. Consumption patterns (years of cannabis use, 30-day point prevalence of cannabis and CBD use, type of consumption) 3. Cannabis use (CUDIT-R) 4. Alcohol abuse (AUDIT-C) 5. Perceived Stress (PSS-10) 6. Comprehensive Inventory of Mindfulness Experience (CHIME) 7. Depression (PHQ-9) 8. Generalized Anxiety (GAD-7) 9. Client Satisfaction 10. Negative effects according to Rozental et al. (2016) 11. Mindfulness Attention Awareness Scale (MAAS) 12. Severity of Dependence Scale (SDS) 13. National Institute on Drug Abuse Screening (NIDA-ASSIST) 14. Drug Abuse Screening Test (DAST-10) 15. Adult ADHD Self-Report Scale (ASRS-V1.1) Some measures are taken at baseline (all but 9 and 10), some after 6 weeks (1, 2, 3, 5, 9, 10, 11, 12) and some after 3 and 6 months follow-up (1, 2, 3, 4, 5, 7, 8, 11, 12, 13) Previous secondary outcome measures: At baseline, after 6 weeks, and at 3 and 6 months follow-up. 1. Cannabis use frequency and amount over the past 7 days according to the "time-line-follow-back" (TLFB) method. 2. Number of days of CBD use in the last 30 days 3. Cannabis use (CUDIT) 4. Alcohol abuse (AUDIT-C) 5. Perceived Stress (PSS-10) 6. Comprehensive Inventory of Mindfulness Experience (CHIME) 7. Depression (PHQ-9) 8. Generalized Anxiety (GAD-7) 9. Client Satisfaction 10. Adverse effects according to Rozental et al. (2016)	—

Measure

Time frame

Current secondary outcome measures as of 24/01/2022: 1. Cannabis use frequency and amount over the past 7 days according to the "time-line-follow-back" (TLFB) method 2. Consumption patterns (years of cannabis use, 30-day point prevalence of cannabis and CBD use, type of consumption) 3. Cannabis use (CUDIT-R) 4. Alcohol abuse (AUDIT-C) 5. Perceived Stress (PSS-10) 6. Comprehensive Inventory of Mindfulness Experience (CHIME) 7. Depression (PHQ-9) 8. Generalized Anxiety (GAD-7) 9. Client Satisfaction 10. Negative effects according to Rozental et al. (2016) 11. Mindfulness Attention Awareness Scale (MAAS) 12. Severity of Dependence Scale (SDS) 13. National Institute on Drug Abuse Screening (NIDA-ASSIST) 14. Drug Abuse Screening Test (DAST-10) 15. Adult ADHD Self-Report Scale (ASRS-V1.1) Some measures are taken at baseline (all but 9 and 10), some after 6 weeks (1, 2, 3, 5, 9, 10, 11, 12) and some after 3 and 6 months follow-up (1, 2, 3, 4, 5, 7, 8, 11, 12, 13) Previous secondary outcome measures: At baseline, after 6 weeks, and at 3 and 6 months follow-up. 1. Cannabis use frequency and amount over the past 7 days according to the "time-line-follow-back" (TLFB) method. 2. Number of days of CBD use in the last 30 days 3. Cannabis use (CUDIT) 4. Alcohol abuse (AUDIT-C) 5. Perceived Stress (PSS-10) 6. Comprehensive Inventory of Mindfulness Experience (CHIME) 7. Depression (PHQ-9) 8. Generalized Anxiety (GAD-7) 9. Client Satisfaction 10. Adverse effects according to Rozental et al. (2016)

—

Countries

Austria, Germany, Switzerland

Outcome results

None listed

Source: ISRCTN (via WHO ICTRP) · Data processed: Feb 18, 2026