[Spanish adaptation and validation of The Adolescent-Cannabis Problems Questionnaire (CPQ-A)].

Cannabis is a widely used substance among adolescents and young adults, but demand for help and treatment from this age group continues to be low. It is therefore essential to develop instruments especially designed for the early detection of problems associated with cannabis use in this population. The purpose of this work is to adapt and validate the CPQ-A (Adolescent Cannabis Problems Questionnaire) for its use as a screening instrument in Spanish population. The sample was made up of 144 young people (71.5% male) aged 16 to 20 (M = 17.12; SD = 1.17) who had used cannabis in the last month and were on some kind of study or training course at various educational institutions in Asturias (a region in northern Spain). Factor analysis of the CPQ-A in this sample provides evidence of a unidimensional structure, with a Cronbach's Alpha of 0.86 for the questionnaire. The evidence also shows that the instrument's convergent validity is good. The CPQ-A score permits discrimination between moderate and excessive cannabis users over the last month, is positively related to score on the CAST (Cannabis Abuse Screening Test), and presents adequate sensitivity and specificity for identifying cases of cannabis abuse and dependence according to the DSM IV-TR criteria. It is also sensitive to young people's degree of concern about cannabis use and the psychopathological effects associated with it. In accordance with the results obtained, the CPQ-A can be considered a useful screening tool for young cannabis users with problems.