PRESENCE IN Charlotte De Kock (Ugent), Pedro Alcântara da Silva (ICS-Ulisboa), Eva Blomme (Ugent), Jerôme Antoine (Sciensano), Ricardo Felisberto (SICAD) European Society for Prevention Research 25th October 2018, Lisbon, Portugal AND PROFILE CHARACTERISTICS OF NON-NATIONAL CLIENTS IN BELGIAN AND PORTUGUESE SUBSTANCE USE TREATMENT A DESCRIPTIVE ANALYSIS