Suicide rates among men aged 15-29 fell by 42%

The study, led by Dr Cameron Stark, also found there had been a reduction in hangings and poisoning by car exhaust fumes as suicide methods.

Use of carbon-cutting catalytic converters on vehicles was found to be one of the reasons.

Dr Stark said more research was needed to confirm a link between the fall and government anti-suicide initiatives.

These include Chooselife, which has launched a new website - believed to be the first of its kind in the world - in an effort to prevent suicides in the Highlands.

We need to do more work before a definite link between rates and initiatives can be drawn

Dr Cameron Stark

Dr Stark also said that though there was a reduction in death rates, this did not mean there was a decrease in suicidal behaviour.

The research team based its analysis on routinely collected information for the period 1980-2004 from the General Register Office for Scotland.

Data showed a 42% reduction in suicide rates among 15 to 29-year-old men, an age group considered particularly vulnerable.

The team said the fall in the suicide rate among young men may be the result of them changing their preferred method of suicide, hanging, to poisoning, which has a less immediate effect.

Younger women

Its report flagged up the launch of various government schemes such as the Scottish suicide prevention strategy, Chooselife, the See Me anti-stigma programme and Breathing Space confidential telephone helpline targeted at young men.

Dr Stark said: "It is tempting to associate the lower suicide rate in younger men, and to an extent in younger women, with these initiatives.

"For instance, Chooselife has requested the media not to report the method of suicide in their reports, but the reduction in cases of hanging seems to pre-date this appeal.

"We need to do more work before a definite link between rates and initiatives can be drawn."