Assessing drug-specific knowledge as a protective factor in illicit substance use: the Heidelberger Drogenbogen (Heidelberg drug scales – HDB)

Abstract

Background: As a modular inventory, the Heidelberger Drogenbogen (HDB) assesses substance-specific knowledge regarding the illicit psychoactive substances cocaine, amphetamines, cannabis, ecstasy, and hallucinogens. This diagnostic tool allows for assessing the level of substance-specific knowledge in most frameworks of prevention.

Objectives: This study outlines basic psychometric parameters of the HDB. Different groups of drug users (clinical versus non-clinical, users versus non-users) are compared concerning their knowledge about psychoactive substances.

Methods: A community sample (recruited at schools, universities and in subcultural contexts [n = 4212]) was compared to a clinical sample (recruited in in- and out-patient drug abuse treatment departments [n = 582]).

Results: Cronbach’s α coefficients (0.61 ≤ α ≤ 0.87) and test–retest correlations (0.81 ≤ r_p ≤ 0.87) indicate that the scales are reliable measures of substance-specific knowledge about drugs. Drug users generally have a higher level of knowledge than non-users. Within the group of users, clinical users display a significantly lower level of knowledge than non-clinical users. This confirms the construct validity of the HDB knowledge modules, thus helping to redefine prevention strategies targeting abstinence as well as less harmful consumption patterns.

• Cannabis
• cocaine
• harm reduction
• Illicit
• substance-use

Acknowledgements

We thank all study participants and staff members in the inpatient and outpatient clinics who supported this study. The authors thank Lisa Mühlhan and all lab members for helping with the data acquisition.

Declaration of interest

This research was supported by the Thyssen Foundation, the Hogrefe publisher and the German National Academic Foundation (Studienstiftung des deutschen Volkes). The study was approved by the ethics committee of the Heidelberg Medical Faculty (No. 218/2005). The authors declare that they have no conflict of interest.