"As shown in Table 4.5 above, in 2010, a total of 4.6% of Spain’s students within the 14-18 age range might be involved in a use of drugs which may cause them some type of problem. The prevalence of problem use, calculated by means of the CAST [Cannabis Abuse Screening Test] scale, reveals an upward trend in Spain within the 2006-2010 time period, despite a slight decline in cannabis use having been record for the same period.
"The upward trend revealed by the results of the CAST scale fits in with the rise recorded in the number of individuals admitted for treatment due to cannabis among minors within the past few years. Hence, the percentage of individuals admitted for treatment among minors related to cannabis was 69.2% in 2005, 72.4% in 2006, 78.4% in 2007, 83.8% in 2008, 84.4% in 2009 and 89.5% in 2010.
"The analysis of the CAST scale on the 2007 ESPAD survey (students ages 15-16 from different European countries) resulted in a 2% problem cannabis use prevalence figure (similar to that recorded in Spain in 2006), using cut-off points similar to those used in the case of Spain. However, even though these are the cut-off points which are used as standard practice, studies have now been published pointing out certain advantages being involved in using lower cut-off points when the CAST scale is used as a screening method for the general population. Hence, the 2011 ESPAD survey recorded a 5% prevalence of problem use when a >2 cut-off point was used."

Source

Government Delegation of National Plan on Drugs (Reitox National Focal Point for Spain), "2012 National Report (2011 Data) to the EMCDDA: Spain: New Development, Trends and in-depth information on selected issues" (Madrid, Spain: DGPNSD, Dec. 2012), p. 123.
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