CANABIC: CANnabis and Adolescents: effect of a Brief Intervention on their Consumption--study protocol for a randomized controlled trial.
BACKGROUND
Cannabis is the most consumed illegal substance in France. General practitioners (GPs) are the health professionals who are most consulted by adolescents. Brief intervention (BI) is a promising care initiative for the consumption of cannabis, and could be a tool for GPs in caring for adolescents who consume cannabis. The aim of the CANABIC study is to measure the impact of a BI carried out by a GP on the consumption of cannabis by adolescents of 15 to 25 years of age.


METHODS
A randomized clustered controlled trial, stratified over three areas (Auvergne, Languedoc-Roussillon, and Rhône - Alpes), comparing an intervention group, which carries out the BI in consultation, and a control group, which ensures routine medical care. The main assessment criterion is the consumption of cannabis by amount of joints per month, at 12 months. The amount necessary to highlight a significant difference between the two groups of 30% of consumption at 12 months is 250 patients (50 GPs, 5 patients per GP; risk α = 5%; power = 90%; intra-cluster correlation coefficient ρ = 0.2; Hawthorne effect = 15%; lost to follow-up rates for GPs = 10% and for patients = 20%). This plan is replicated for the three areas, and therefore a total of 750 patients are expected.The secondary criteria for judgment are the associated consumption of tobacco and alcohol, the perception of the consequences of consumption, and the driving of a vehicle following consumption.


CONCLUSIONS
Research about BI for young cannabis users is underway. The aim of the CANABIC study is to validate a BI suited to adolescents who consume cannabis, which may be performed in the general practice. This would provide a tool for their treatment by a GP, which could be widely distributed during initial or further medical training.


BACKGROUND
CANABIC is a randomized clustered trial (NCT01433692, registered 2011 Sept 12), PHRC funded: Clinical Research Hospital Program (Governmental Fund, Health Ministry). Date first patient randomized: March 2012.
Department of General Medicine, Faculty of Medicine of Clermont-Ferrand, 28 Place Henri Dunant, 63000 Clermont-Ferrand, France. catherine.laporte@udamail.com.
Catherine
C
Laporte
Hélène
H
Vaillant-Roussel
Bruno
B
Pereira
Olivier
O
Blanc
Gilles
G
Tanguy
Paul
P
Frappé
David
D
Costa
Yoann
Y
Gaboreau
Mélanie
M
Badin
Laurent
L
Marty
Gilles
G
Clément
Claude
C
Dubray
Bruno
B
Falissard
Pierre-Michel
PM
Llorca
Philippe
P
Vorilhon
D000293:Adolescent; D000294:Adolescent Behavior; D000328:Adult; D000428:Alcohol Drinking; D001334:Automobile Driving; D002985:Clinical Protocols; D005602:France; D058006:General Practice; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D002189:Marijuana Abuse / Q000175:diagnosis / Q000517:prevention & control* / Q000523:psychology; D008385:Marijuana Smoking / Q000517:prevention & control* / Q000523:psychology; D010465:Perception; D011614:Psychotherapy, Brief; D012107:Research Design; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult