As adolescents become more autonomous so the influence of
the peer group becomes more important and family influences
wane (Bremner et al., 2011). Adolescence sees a clustering of
risk-taking behaviours such as smoking, drinking, drug-taking
and sexual activity. Peer effects on risk-taking are strong in
this age group, and adolescents affiliated with substance-using
peers are at greater risk of engaging in similar behaviours
themselves (Gardner and Steinberg, 2005)