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INCA - Intervention and Neuropsychology in Cannabis Abuse

Targeted Interventions in Cannabis Abuse: Focus on Decision Making (INCA)

Status
UNKNOWN
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00279604
Enrollment
160
Registered
2006-01-19
Start date
2005-07-31
Completion date
2007-10-31
Last updated
2007-04-20

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

Conditions

Marijuana Abuse

Brief summary

INCA (Intervention and Neuropsychology of Cannabis Abuse) is a study combining two research goals. One is to study efficacy of a short intervention the 'Problem Profile Intervention', which utilizes individual feedback from a 'substance problem check-up'. Subjects will randomly receive the 'Problem Profile Intervention' or the WHO Brief Intervention, a brief intervention, which has been shown to be efficacious. Currently efficiency studies are under way. The WHO Brief Intervention has been translated into German by our group. In contrast to most other cannabis intervention studies the current study is focussed on cannabis abusers not so much cannabis-dependent subjects. A total of 160 subjects are to be recruited. Half of them will randomly receive either the Problem Profile Intervention or the WHO Brief Intervention (active control). A total of 25% of subjects from each group will be placed on a 3 months waiting list before receiving the intervention (inactive control). Intervention outcome will be assessed three months, six month and 12 months after the intervention. We hypothesize cannabis use to be reduced by 25% by the 'Problem Profile Intervention'. The second aim of the study is to study mechanism of substance abuse. Initial results from own studies and data from other groups point to executive cognitive functions as a subtle but important factor that can be compromised in cannabis users (Verdejo-Garcia et al., 2004; Garavan and Stout, 2005). Using an fMRI-study, we intend to examine a subgroup of our subjects on a specific aspect of executive functioning that has recently received major interest in drug research: Decision-making capability, or risk-taking behaviour, respectively (e.g. Ernst and Paulus, 2005).

Interventions

BEHAVIORAL'Problem Profile Intervention' vs. WHO-Brief Intervention

Sponsors

German Federal Ministry of Education and Research
CollaboratorOTHER_GOV
University Hospital, Bonn
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
16 Years to 36 Years
Healthy volunteers
Yes

Inclusion criteria

* ASSIST-Score for cannabis consume ≥ 4 ≤ 26 * german mother tongue (or comparable level)

Exclusion criteria

* major current psychiatric disorder (e.g. psychosis) * addiction to other illegal drugs or alcohol * recent or current intravenous drug use * CNS-affecting medication * current psychotherapy, other treatment for substance use disorder

Design outcomes

Primary

MeasureTime frame
Cannabis consumption,
motivational change

Secondary

MeasureTime frame
ASSIST-Score

Countries

Germany

Contacts

Primary ContactChristian G Schuetz, MD MPH
christian.schütz@ukb.uni-bonn.de+49 228 287 9664

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026