Netherlands National Drug Monitor - Research and Documentation ...

Figure 2.2 Cannabis use among secondary-school pupils aged 12 to 18 since 1988
30
% Ever use
30
% Current use
25
25
20
20
15
15
10
10
5
5
1988 1992 1996 1999 2003 2007
1988 1992 1996 1999 2003 2007
Boys Girls Total Boys Girls Total
Percentage of ever users (left) and last month (right).
Source: Dutch National School Survey, Trimbos Institute.
Age
• Cannabis use increases among school-goers with age. In 2007, few school-goers
aged 12 had tried cannabis – only one in fifty (2%). By the age of 16, almost one in
three had ever tried cannabis (30%).
• The age at which school-goers first used cannabis dropped between 1988 and 1996,
after which it stabilised (Monshouwer et al., 2005). The percentage of boys who
had already tried cannabis at a very young age (≤14 years) remained stable between
1996 and 2003 (21%) and declined between 2003 and 2007 from 21 to 13 percent.
Among 14-year old girls, the decline in ever use of cannabis between 2003 and 2007
was less marked and was not significant (from 16% to 12%).
• The Antenne Monitoring Station in Amsterdam found that the average age of onset
for ever cannabis use among school-goers of western ethnicity rose from 13.5 in 1997
to 14.2 in 2007 (Nabben et al., 2008).
• An early age of onset for cannabis use is associated with an increased risk of later
developing mental health disorders, cannabis dependency, use of hard drugs and
possibly cognitive disorders (CAM, 2008). The precise mechanisms involved are not
fully known (e.g. effects of cannabis on the developing brain, susceptibility and/or
social processes).
2 Cannabis
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