A report from the Prime Minister's chief science adviser says raising the drinking age to 21 and increasing alcohol prices are two of the most effective ways to address youth drinking problems.

Professor Sir Peter Gluckman yesterday released a paper on social problems facing young people, which Prime Minister John Key requested after the death from alcohol poisoning of King's College student James Webster in May last year.

The Improving the Transition paper comes as alcohol law reforms making their way through Parliament will require MPs to decide whether to increase the alcohol purchasing age to 20 or create a 'split age' of 18 in pubs and on-licences and 20 for off-licence sales. Mr Key favours the split age.

The Gluckman report will put more pressure on him to go further in toughening up the alcohol laws - his Government is already under pressure for refusing to move on Law Commission alcohol reform recommendations to increase alcohol taxes and lower the drink driving limit for adults.

In a chapter on teenage drinking, Christchurch Health and Development Study academics Professor David Fergusson and Professor Joseph Boden said the most effective reforms would be a "substantial rise" in the drinking age to 21, higher alcohol prices and more limited availability.

A chapter on youth suicide also advocated limiting access to alcohol and making it less affordable.

"If the opportunity to reduce drinking by implementing recommendations [of the Law Commission report] is missed, many young lives may be lost that could otherwise have been saved."

The Prime Minister said the report was "weighty" and covered many problems that were difficult to solve. "They have been problems that have manifested themselves for a long time in New Zealand."

He had already asked for further work to be done on mental health and youth suicide - an area in which the report said there was a "woefully deficient" services for teenagers.

Mr Key said he intended to throw the weight of his office behind that issue.

"That will cost money but it's a worthy area and we will go away and do more on it."

The report said although about one in five teenagers had depression, three-quarters of them did not get treatment. It proposed greater screening for depression and more investment in treatment, as well as alternatives such as online therapy.

The authors unanimously called for some political consensus and long-term commitment for programmes that were proven as effective, rather than ruled by dogma. It said getting real change required prolonged effort over several electoral cycles "and cannot be held hostage to adversarial politics".

The Prime Minister disagreed with the report on one issue - boot camps. It said these and military-style camps were generally not effective and it was difficult to assess why some worked well but others did not.

Mr Key said boot camps were effective and he had no plans to halt them.

* More specialist adolescent mental health workers.
* National strategy to reduce depression in teenagers.
* Increase price of alcohol and restrict availability.
* Stricter drink-driving laws.
* Restrictions on media reporting of suicide should remain.
* School-based courses on drinking and drugs generally ineffective and need review.
* Early intervention for at-risk families will prevent many problems later.