Online Brief Advice Intervention for Heavy Cannabis Users

NCT07379736 | Recruiting

• 1 other identifier: REMAS: 49272
• Study Type: interventional
• Target: 100
• Locations: 1 country
• Sites: 1

Brief Summary

This project will evaluate whether a brief online intervention focused on cannabis withdrawal can increase awareness and insight about cannabis use disorder among daily cannabis users. The study will employ a randomised controlled trial design comparing an intervention consisting of a short educational video on cannabis withdrawal and personalised feedback on the Cannabis Withdrawal Scale, against a control condition of a relaxation video and mood questionnaire. The investigators will aim to recruit at least 100 daily cannabis users (minimum 25 days of cannabis use /month and minimum 3.5g cannabis/week \[low-medium daily use\]) through Prolific, an online research participant platform. Potential participants will complete a brief screening questionnaire (1 minute) to confirm that participants meet inclusion criteria, before randomisation. The experiment will last 10-15 minutes and will include baseline demographic and substance use measures, the intervention or control condition, and outcome measures. The primary outcome will be cannabis use awareness and insight as measured by the Substance Use Awareness and Insight Scale (SAS). Secondary outcomes will include intention to change cannabis use. This study aims to determine whether a short online intervention can increase awareness about cannabis withdrawal among heavy users. If successful, subsequent studies will be designed to assess these outcomes over the longer-term.

Conditions

Cannabis User

Keywords

Cannabis; Brief Intervention

Outcome Measures

Primary Outcomes (1)

• Substance (cannabis) use awareness and insight scale (SAS)

  Measured by the Substance Use Awareness and Insight Scale, designed to assess awareness in substance use disorder. Minimum value = 0, maximum value 70. Higher score = worse outcome, less insight and awareness.

  Day 1

Secondary Outcomes (1)

• Intention to change cannabis use

  Day 1

Study Arms (2)

Educational video

EXPERIMENTAL

A short educational video on cannabis withdrawal and personalised feedback on the Cannabis Withdrawal Scale

Other: Educational video

Relaxation video

ACTIVE COMPARATOR

A relaxation video and mood questionnaire

Other: Relaxation video

Interventions

Relaxation video OTHER

Relaxation video and mood questionnaire with personalised feedback

Also known as: Mindfulness video, Meditation video, Peaceful video

Relaxation video

Educational video OTHER

Short educational video on cannabis withdrawal and personalised feedback on the Cannabis Withdrawal Scale.

Also known as: Learning video, Informational video

Educational video

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Adults (\>18 years)
• Daily/near daily cannabis users (25+ days/month, min. 3.5g/week)
• Sufficiently fluent in English

You may not qualify if:

• Participant is prescribed medical cannabis by a healthcare professional

Sponsors & Collaborators

• King's College London: lead

Study Sites (1)

Denmark Hill

London, Greater London, SE5 9RS, United Kingdom

RECRUITING

MeSH Terms

Conditions

Marijuana Abuse

Condition Hierarchy (Ancestors)

Substance-Related Disorders; Chemically-Induced Disorders; Mental Disorders

Central Study Contacts

Edward Chesney, MRCPsych

CONTACT

02078365454; edward.chesney@kcl.ac.uk

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: OUTCOMES ASSESSOR
• Purpose: OTHER
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 22, 2025
• First Posted: January 30, 2026
• Study Start: October 16, 2025
• Primary Completion (Estimated): September 1, 2026
• Study Completion (Estimated): September 1, 2026
• Last Updated: January 30, 2026

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

GB (1)