Properties of the Cannabis Abuse Screening Test (CAST) in the general population

Abstract

This paper explores the DSM-IV latent structure of cannabis users (especially its invariance towards gender and age) and assesses the psychometric properties of the Cannabis Abuse Screening Test (CAST) by confrontation with the theoretical diagnoses [dependence and cannabis use disorders (CUD)] and the latent class structure of the DSM-IV. The random sample comprised 550 French cannabis smokers aged 15-62 years interviewed by telephone. DSM-IV diagnoses were assessed with the Munich Composite International Diagnostic Interview. Internal structures of both instruments were assessed using factor analysis and latent class analysis. Optimal CAST cutoffs were determined by sensitivity, specificity and area under the receiver operating curve (AUC). CAST and DSM-IV were unidimensional (Cronbach's α = 0.742 and 0.752, respectively), although a two-factor solution showed a better fit for the CAST. CAST cutoffs for screening CUD and dependence were three (AUC = 0.851) and five (AUC = 0.868), respectively. DSM-IV latent class structure varied only marginally in age and gender. Three classes of cannabis smokers were determined, ordered along a continuum of symptoms: non-symptomatic (61.1%), moderate (32.9%) and severe (6.0%). CAST cutoff scores for screening moderate/severe and severe were, respectively, three (AUC = 0.869) and eight (AUC = 0.952). Results are compared to those obtained in previous CAST studies and discussed in line with the DSM-5.

Age Invariance of the Cannabis Abuse Screening Test in a Probabilistic Sample of Cannabis Users

“…This age partial measurement invariance may be a reason why there is some variation of the optimal score threshold of the CAST identified in populations that differed in age distribution. Indeed, in adolescents aged 17–19, when considering the classical DSM-IV diagnoses of Cannabis use disorder (either dependence or abuse) and dependence, the optimal thresholds were 3 and 4 respectively [3], while in the general population (age 15–62), the corresponding thresholds were 3 and 5 respectively [8]. When considering the DSM-5 diagnoses of moderate/severe and severe Cannabis use disorder, the optimal thresholds were 3 and 7 in adolescents aged 17–19 [4], while the corresponding values in the general population aged 15–64 were 5 and 8 [9].…”

“…The CAST factor structure was assumed to be bi-dimensional as found in previous studies [1, 8-10]. Age measurement invariance was tested using mgCFA and the weighted least squares means and variance adjusted estimator and the classical 3-step sequence was used to investigate configural, metric, and scalar invariance [13, 14].…”

“…It was initially designed in France to describe and screen problematic use of cannabis in youth [2-4] but has been used afterwards in various settings including adults [5-8]. The CAST comprises 2 factors: the “Problems” (items 3–6) and “Non-recreational use” (items 1 and 2) factors.…”

Diseño y validación de una escala de intención de consumo de cannabis (CUIQ) para adolescentes

“…También se puso a prueba el modelo predictivo TAP en relación al consumo de cannabis mediante el desarrollo de path analysis. Finalmente, los análisis de la curva COR con los criterios de haber consumido cannabis en los últimos 30 días y puntuación de corte 3 de CAST (Legleye et al, 2015) permitieron establecer puntos de corte para el riesgo de consumo y el riesgo de presentar problemas derivados del consumo de cannabis, respectivamente. Se utilizaron los paquetes estadísticos SPSS© Versión 22 y EQS© Versión 6.3.…”

“…Los análisis de las curvas COR (Tabla 5, Figuras 3 y 4) indican que la intención es el factor que mejor clasificó tanto el consumo como el riesgo de problemas debidos al consumo de cannabis medido como punto de corte 3 en CAST (Legleye et al, 2015). Las áreas bajo la curva en intención fueron altas (0,93 respecto al consumo de cannabis y 0,87 respecto al riesgo medido con CAST).…”