Good parenting could be a reason behind a drop in teenage cannabis use.
A study published in the Medical Journal shows a long-term decline in cannabis use, and linked it to a wider decline in the use of alcohol, tobacco and drugs for high school students.
It also shows consistent decline in the use of drugs, alcohol and tobacco.
Otago University public health researcher Jude Ball told Andrew Dickens parents are much more involved in their teenagers' lives.
She says they are less likely to turn a blind eye to use of substances like alcohol.
“A lot of younger people now have more structure in their day. That means there are fewer opportunities for risky behaviour.”
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