Rewards for Cannabis Abstinence-study
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: Abstinence-focused Contingency Management (CM) - stand alone, Standard Outpatient Cognitive Behavioural Therapy (CBT).
- Who it may be relevant to
- Registry conditions: Cannabis Use Disorder. Basic parameters: 16 years — 22 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Netherlands
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
Unsure about the terms? Read our patient guide →
Official title
The Cost-effectiveness of Contingency Management Compared to Standard Cognitive Behavioral Treatment for Treating Cannabis Use Disorder in Youth: A Randomized Controlled Trial
Overview
The goal of this clinical trial is to investigate the (cost-)effectiveness of contingency management (CM) compared with Cognitive Behavioural Therapy (CBT) for the treatment of cannabis use disorder (CUD) in youth (16-22 years). The main questions it aims to answer are: * What is the efficacy of 12 weeks outpatient CM versus CBT in youths with a CUD, in terms of cannabis abstinence during the intervention period? * What is the long-term efficacy of CM versus CBT at 6- and 12-months follow-up (FU)? * What is the cost-effectiveness of CM versus CBT at 12-months FU from a societal perspective? Study hypotheses are: 1\. CM will result in more cannabis-abstinent days than CBT during the intervention; 2. CM is more effective and cost-effective than CBT at 12 months follow-up. Eligible patients (n=154) will be randomly assigned to either 12 weeks of outpatient CM or CBT. Assessments are conducted by trained research-assistants at baseline, after 6, 12, 26 and 52 weeks, and twice-weekly during treatment and consist of questionnaires, a computer task and collection of urine samples. Primary endpoint is the number of biochemically verified cannabis abstinent days in the 12-week treatment period. Key secondary endpoint: Treatment response: 50% or more reduction in cannabis use days in the past 4 weeks, compared with baseline. The primary outcome will be modelled in the intention-to-treat population in a (negative binomial) regression analysis with treatment group as independent variable and stratification variables as covariates. Cost-effectiveness and cost-utility analysis (CEA; CUA) will be performed from a societal perspective. CEA: Treatment response is the central clinical endpoint for calculations of incremental costs per responder. CUA: Incremental costs per QALY (based on EuroQoL).
Interventions
- Behavioral Abstinence-focused Contingency Management (CM) - stand alone
Outpatient abstinence-focused contingency management (CM) as stand-alone treatment (12 weeks). Monetary incentives (vouchers) are provided for cannabis abstinence, based on twice-weekly rapid test urinalysis and an escalating reward scheme with bonuses. Urine samples are collected at the treatment centre during 15-minute sessions by a trained CM-practitioner. For each cannabis-negative urine, patients receive a monetary voucher starting at €5 and escalating to max. €35 after eight consecutive we - Behavioral Standard Outpatient Cognitive Behavioural Therapy (CBT)
CBT is the usual care first line treatment for CUD in youth, in the Netherlands. CBT for CUD is focused on learning cognitive, emotional, motivational and behavioral skills to reduce or cease cannabis use, and generally consists of 12 once-weekly 60-minute sessions and 'homework' exercise assignments, provided by a psychologist. Youths receive 12 weeks of outpatient usual care CBT consisting of once-weekly 60-minute sessions according to the standard CBT youth protocol by a trained psychologist
Primary outcome measures
- Cannabis-abstinent days (biochemically verified) [Time frame: 12 weeks]
Secondary outcome measures (3)
- long-term 'treatment response' [Time frame: 52 weeks]
- Incremental costs per treatment responder [Time frame: 52 weeks]
- Incremental costs per QALY [Time frame: 52 weeks]
Eligibility criteria
Inclusion criteria
- Youths (16-22 years) seeking treatment for a primary CUD
- Regular cannabis use (≥14 days) in past 4 weeks
- Intention to cease cannabis use during intervention
- Able and willing to attend the treatment center and submit urine samples under supervision twice-weekly
- Informed consent.
Exclusion criteria
- Health contra-indications (e.g., acute psychosis/suicidality)
- Insufficient Dutch language.
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Parallel assignment
- Masking
- Open label
- Primary purpose
- Treatment
Study locations
Netherlands · 5 centers
- Jellinek, Stichting Arkin B.V. — Amsterdam
- IrisZorg — Arnhem
- Antes Youz — Rotterdam
- Brijder — The Hague
- Novadic-Kentron — Vught
Identifiers
NCT: NCT05836207 · 10390012110082