Treatment Demand Indicator [TDI-45]

Description

The Treatment Demand Indicator (TDI-45) is a structured instrument used to collect standardized information about individuals who enter counseling or treatment services for problems related to substance use.

Its development is associated with the European effort to harmonize the recording of treatment demand data through cooperation involving the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), the Pompidou Group, and representatives of EU Member States.

Within the Greek context, the instrument has been used in addiction treatment and counseling services to systematically record the characteristics and treatment needs of individuals seeking help.

Purpose

The primary purpose of the TDI-45 is to provide a standardized methodology for collecting data on people who come into contact with treatment services because of substance-use-related problems.

The instrument enables the recording of information concerning:

• sociodemographic characteristics,
• patterns of substance use,
• high-risk behaviors,
• family history,
• physical and mental health,
• involvement with the legal system,
• treatment history and treatment needs.

The resulting data may also be used to monitor trends in substance use and treatment demand over time.

Structure

According to the provided material, the TDI-45 includes 45 structured questions covering areas such as:

• treatment contact and admission details,
• sociodemographic information,
• substance-use information,
• high-risk behavior,
• family history,
• health-related information,
• involvement with the law,
• military service,
• interview assessment,
• summary of treatment continuity and progress.

The reference period mainly concerns the individual’s condition during the 30 days prior to treatment entry.

Scoring

The provided material indicates that assessment may include domain scores ranging from –3 to +3, with negative values reflecting deterioration and positive values reflecting improvement.

It also refers to an overall focal score ranging from –9 to +9.

However, because the TDI primarily functions as a standardized treatment-demand monitoring and data-recording system, any numerical scoring or interpretation should follow the specific protocol or version of the instrument being used.

Data Analysis and Use

Analysis of TDI-45 data may include descriptive statistics concerning the characteristics of people entering treatment, patterns of substance use, and identified treatment needs.

Comparisons may also be made across different groups, treatment services, or time periods, while trend analyses can be used to examine changes in treatment demand.

At the public health level, TDI data can contribute to the assessment of the extent and development of substance-use-related problems, particularly when interpreted alongside other epidemiological indicators.

Validity and Reliability

According to the provided material, the TDI-45 demonstrates satisfactory validity and reliability.

Content validity is supported by the involvement of international experts in the development of the protocol and by its coverage of major domains related to substance use and treatment.

The material also reports evidence of construct and criterion-related validity through associations with other established assessment instruments, such as the Addiction Severity Index (ASI) and EuropASI.

Regarding reliability, the material reports Cronbach’s alpha values above 0.70 for individual sections and test-retest coefficients above 0.80.

Applications

The TDI-45 may be used in:

• addiction treatment and counseling services,
• substance-use treatment programs,
• epidemiological surveillance,
• public health research,
• assessment of treatment needs,
• monitoring trends in treatment demand.

Its main value lies in the production of comparable and systematically organized data, which may be used at clinical, national, and European levels.

References

European Monitoring Centre for Drugs and Drug Addiction. (2012). Treatment Demand Indicator (TDI) Standard Protocol 3.0: Guidelines for Reporting Data on People Entering Drug Treatment in European Countries. Publications Office of the European Union.

Pompidou Group, Council of Europe, & European Monitoring Centre for Drugs and Drug Addiction. (2000). Treatment Demand Indicator (TDI): Standard Protocol 2.0.

University Mental Health Research Institute (UMHRI) – Greek Documentation and Monitoring Centre for Drugs (EKTEPN). (2004). Treatment Demand Indicator for Drug Users (2nd ed.). Athens: UMHRI.