[Comparison of European therapies for cannabis addiction among adolescents]

In European countries, cannabis abuse and dependence among adolescents has become a public health priority. Since 2002, studies have shown that persons seeking treatment for cannabis use are increasing. Over the past ten years, the involvement of many structures working on this topic has permitted an expansion and a diversification of treatment protocols. Moreover, international scientific studies, mainly conducted in the United States, have demonstrated the effectiveness of therapies based on motivation interviews, cognitive behavioral therapy (CBT) and family approach. Among these treatments, the multi-dimensional family therapy (MDFT), developed by the team of Professor Liddle in Miami, showed great efficiency in young adolescents with cannabis abuse problems. Five European countries therefore decided to build a randomized control study (RCT) comparing MDFT to the treatments that were commonly used. For the purpose of the research, the usual treatments had to be described and were named treatment as usual (TAU). Besides the obvious interest of implementing MDFT in Europe, it seems equally important to highlight the investment that has been made by all the European structures. The goal of this article is to describe and share the previous experience of all centers that have participated in the INCANT trial including the Netherlands, Germany, Belgium, Switzerland and France in the field of cannabis adolescent abusers.

To describe and compare European treatment as usual (TAU), we visited each structure to meet and to interview the teams regarding their practices. To perform these interviews, we used a semi directive questionnaire we had built previously. We completed the therapist's interviews with their written clinical protocol (when they had one) and a video/audiotaped session or written session. Data collection took place in five addiction centers: Therapy laden in Germany, Phoenix foundation in Switzerland, Cannabis clinic in Belgium, Palm Huis in Holland and Emergence and CEDAT in France.

In terms of monitoring arrangements, there are many similarities between the European TAU. Indeed, all European centers were practicing individual therapy mainly focusing on the adolescent, and therapists were involving parents. In almost all European countries, the teenager was seen at one session per week, the parents were seen once a month and the duration of the therapy was about 6 months. The interview analysis has revealed that between countries, despite therapeutic techniques and differences in psychopathological approach, a global care process remained quite common. The therapeutic process, in all countries, was organized in two phases: build the therapeutic alliance and assess the situation with the adolescent, and help to coach him/her to enhance changes.

The comparison of the TAU highlights the difficulties to see differences between models of psychotherapies. Are the psychotherapies really different or is it just a matter of the therapists, experience and good will? The debate is open and articles have shown arguments for both hypotheses. The analysis of our TAU indeed shows a common base, but as therapists started to formalize what they usually do, differences appear. The Incant study, in which TAU was compared to a formalized family therapy, clearly indicates differences between therapies, but only with heavy cases. Perhaps the more cases became complicated, the more there's a need for formalization and of course this will lead to differences between models.