Development and initial validation of a reliable German self‐report measure to assess acute cannabis intoxication‐effects (CanTox‐17)

Abstract

Objectives Both positive and negative including psychotic‐like cannabis intoxication effects are well‐established. Yet, consequences for consumption patterns, addictive behavior or psychotic developments are poorly researched in general, in Germany not at all. Thus, objective was to develop the first German‐language questionnaire operationalizing acute cannabis intoxication effects, based on the original “Cannabis Experience Questionnaire” (CEQ). Methods After expert translation of the CEQ, items related to acute intoxication effects were presented to a sample of 537 cannabis users. Four‐ and five‐factorial solutions of explorative factor analysis with a randomly split sub‐sample 1 were cross‐validated by confirmatory factor analysis on sub‐sample 2. Results After content review of factors and analysis of external validity, a 17 item four‐factorial model was approved. Factors are (1) “paranoia/dysphoria”, (2) “confusion/disorientation”, (3) “euphoria/creativity”, (4) “psychosis‐like/loss of reality”. Model fit is satisfactory (RMSEA = 0.058, SRMR = 0.065, CFI = 0.929, TLI = 0.914). Correlations with corresponding external measures support construct validity. Conclusions The present questionnaire is a time‐efficient, valid and reliable instrument. Thus, predictors of different cannabis intoxication effects can be analysed for the first time in German‐speaking area, as well as their significance for substance use or psychosis risk.

Predictive impact of different acute cannabis intoxication effects with regard to abstinence motivation and cessation of use

“…Developed initially by Barkus and colleagues 32 , different English-language factor solutions have been subsequently published 31 , 33 , 34 . The German version was developed by our group 20 and it consists of three negative dimensions and one positive dimension of acute cannabis intoxication effects: (1) “psychotic-like experiences/loss of reality” (feeling threatened, hearing voices, losing ones sense of reality, feeling like going crazy); (2) “paranoia/dysphoria” (feeling paranoid, anxious, nervous, depressed); (3) “confusion/disorientation” (speech becoming slurred, time slowing down, disturbed in thinking, not aware of what was going on); (4) “euphoria/creativity” (understanding the world better, feeling energized, full of ideas and more creative). Items were scored on a Likert scale with five graduations.…”

“…Items were scored on a Likert scale with five graduations. Since CanTox-17 was just developed and evaluated within in a recent study 20 , the presented factor structure is to be considered as preliminary result. So, we again analyzed and replicated sufficient goodness-of-fit indices of the instrument and the internal consistency of the factors (cronbach´s alpha).…”

“…The corresponding type of craving is called relief craving, in contrast to reward craving, the hedonistic urge to use drugs 17 . The disregard of acute intoxication effects is also reflected by the fact that in German-speaking countries it was not even possible to operationalize these effects until the recent publication of a corresponding instrument 20 . However, in recent years, international research has turned to the subject, whose significance can be derived from the theory of operant learning: Accordingly, acute consequences of a behavior explain whether or not the behavior will be exhibited again, and the more immediately a reinforcement or punishment follows a behavior, the more predictively effective is the operant effect 21 .…”