The Prime Minister's chief science adviser says there is no evidence government programmes for problem teenagers such as bootcamps, restorative justice and teaching life skills are working.
Sir Peter Gluckman on Wednesday presented the results of an 18-month study commissioned by John Key into high levels of teen suicide, drug use, delinquency and pregnancy.
Sir Peter says many government programmes are not based on evidence, while other programmes proven to be effective have not been put in place.
He says he had assumed that high school courses about sex, drugs and alcohol, as well as those teaching life skills were effective - but the evidence shows they are not.
The report also finds wilderness experiences, boot camps and restorative justice programmes generally do little to help teenagers and they need a thorough assessment.
Prime Minister John Key has welcomed the report on Wednesday, but insists the bootcamps are working.
"We with our own eyes can see that actually, it's successfully transitioning long-term unemployed youth into work. The results speak for themselves - a great many of those young people do transition into training or work."
Mr Key says far from backing away from the camps, the Government is actually putting more money into them.
'Large holes' in programmes
Sir Peter says there are large holes in programmes for teenage depression and interventions in early childhood.
A team of child development academics and clinical experts trawled the New Zealand and international scientific literature to compile a summary of teenage problems and initiatives to tackle them.
Sir Peter's report suggests a major overhaul of Government programmes is required.
"Our research shows that many programmes have been introduced, albeit with good intent, that are unlikely to succeed as they're not supported by the evidence base, whereas other approaches likely to be effective are not being implemented."
The report finds the risk of young people undertaking impulsive and anti-social behaviour is greatly affected by experiences earlier in life, especially in the early childhood years.
It says more attention must be given to teenage depression and how to restrict young people's access to alcohol and drugs.
The comprehensive research summary is believed to be the first of its type in the world.