title: Treatment for substance use disorders: the Belgian Treatment Demand Indicator registration protocol.
abstract: BACKGROUND
  Registration of patients with substance use disorders is of key importance to get insights and to study trends in patients characteristics and substance use patterns. The Treatment Demand Indicator (TDI) is gathering this information at European level since 2000. In Belgium, this registration started at national level in 2011 and an increasing number of facilities of different types are participating in this data collection since then.
  
  
  METHODS
  This surveillance register collects information on every treatment episode started by patients for their substance use disorder. Information is collected on socio-demographic characteristics of the patient, treatment history and substance use patterns. Patients are identified uniquely using their national identification number in order identify multiple episodes followed by a same person. A large range of treatment facilities have the possibility to participate in this registration to allow a wide coverage of the population.
  
  
  CONCLUSIONS
  The objective of the paper is to facilitate the use of data by authorities or researchers by correctly describing all aspects of the indicator. The case definition, the variables collected and the way data should be reported are of key importance to use and interpret the data correctly. An overview of the data registered in 2014 gives also an idea of the content of the database. The article also pictures the strengths and limitations of the register and foresees some future improvements.
authors.affiliation: WIV-ISP: Scientific Institute of Public Health, Brussels, Belgium, Rue Juliette Wytsmanstraat, 14, 1050 Brussels, Belgium.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Antoine
authors.affiliation: WIV-ISP: Scientific Institute of Public Health, Brussels, Belgium, Rue Juliette Wytsmanstraat, 14, 1050 Brussels, Belgium.
authors.forename: Karin
authors.initials: K
authors.lastname: De Ridder
authors.affiliation: WIV-ISP: Scientific Institute of Public Health, Brussels, Belgium, Rue Juliette Wytsmanstraat, 14, 1050 Brussels, Belgium.
authors.forename: Els
authors.initials: E
authors.lastname: Plettinckx
authors.affiliation: WIV-ISP: Scientific Institute of Public Health, Brussels, Belgium, Rue Juliette Wytsmanstraat, 14, 1050 Brussels, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Blanckaert
authors.affiliation: WIV-ISP: Scientific Institute of Public Health, Brussels, Belgium, Rue Juliette Wytsmanstraat, 14, 1050 Brussels, Belgium.
authors.forename: Lies
authors.initials: L
authors.lastname: Gremeaux
keywords: Alcohol; Illicit drugs; Protocol; Registration; Substance use disorder; Treatment