LDQ

Overview

The Leeds Dependence Questionnaire (LDQ) is a 10-item self-report tool developed to comprehensively evaluate substance dependence across various classes of substances. Originally devised by Edwards and Gross in 1976 and refined by Edwards in 1986, the LDQ aims to capture the core features of the dependence syndrome without being specific to any particular substance. This makes it a versatile instrument for assessing dependence on substances such as alcohol and other drugs.

Purpose

The LDQ aims to:

• Identify the degree of substance dependence
• Provide a comprehensive assessment applicable to various substances
• Support clinical and research settings by offering a reliable measure of dependence

Structure

The LDQ assesses dependence through a set of criteria that includes:

• Preoccupation: The individual’s focus on obtaining and using the substance
• Salience: The importance of the substance in the person’s life
• Compulsion to Start: The urge to begin using the substance
• Planning: The effort put into planning substance use
• Maximizing Effect: Behaviors aimed at enhancing the substance's effects
• Narrowing of Repertoire: Reduced engagement in activities not related to substance use
• Compulsion to Continue: The urge to continue using the substance
• Primacy of Effect: The substance's dominant influence over the individual’s behavior
• Constancy of State: Maintaining a steady level of substance use
• Cognitive Set: The mental focus on substance use and related thoughts

Applications

• Clinical Use: Clinicians use the LDQ to assess the severity of substance dependence, aiding in diagnosis and treatment planning.
• Research Use: Researchers employ the LDQ to study substance dependence patterns, evaluate intervention effectiveness, and explore correlations with other psychological conditions.

Psychometric Properties

The LDQ has demonstrated strong psychometric properties:

• Internal Consistency: The LDQ exhibits high internal consistency, as indicated by a Cronbach’s alpha coefficient of 0.94, ensuring reliable measurement across its items.
• Test-Retest Reliability: With a coefficient of 0.95, the LDQ reliably captures changes in dependence over time.
• Validity: The LDQ has shown satisfactory concurrent, discriminant, and convergent validity, aligning closely with diagnostic frameworks such as the International Classification of Diseases (ICD-10) and the Diagnostic and Statistical Manual of Mental Disorders (DSM).

Translation and Adaptation

The LDQ has been translated into multiple languages and adapted for use in different cultural contexts, enhancing its global applicability and utility.

Conclusion

The Leeds Dependence Questionnaire (LDQ) is a valuable tool for identifying and quantifying substance dependence across a range of substances. Its robust psychometric properties and sensitivity to changes in dependence severity make it an essential instrument for clinicians and researchers. By providing a reliable and comprehensive assessment, the LDQ contributes to improved understanding and treatment of substance use disorders.