Washington: A first-of-its kind study on Internet and suicides has found that a net search throws up more sites that detail methods of self-annihilation than those offering help and support.

The study also concludes that people bent on taking their lives are most likely to find sites that offer detailed and factual methods of killing themselves rather than sites that discourage them.

Researchers from the universities of Bristol, Oxford and Manchester replicated a typical search, visiting popular websites like Google, Yahoo, MSN and Ask.

They analysed the first 10 sites from each search, giving a total of 480 hits. Altogether 240 different sites were found of which nearly half provided some information about methods of suicide.

Nearly a fifth of hits - about 90 - were for dedicated suicide sites, of which half were judged to be encouraging, promoting or facilitating suicide.

Sixty-two sites focussed on suicide prevention or offered support and 59 sites actively discouraged suicide.

Almost all dedicated suicide and factual information sites provided information about methods of suicide. But, a fifth of support and prevention sites and over half of academic or policy sites, and all news reports of suicides also provided information about methods.

Overall, Google and Yahoo retrieved the highest number of dedicated suicide sites, while MSN had the highest number of prevention or support sites and academic or policy sites.

In addition, the three most frequently occurring sites were all pro-suicide, whereas the information site Wikipedia was fourth. All top four sites evaluated methods of suicide including detailed information about speed, certainty, and the likely amount of pain associated with each method.

Self-regulation by Internet providers and use of filtering software by parents to block sites are the main approaches to reducing potential harm from suicide sites.

However, efforts to remove some of the most detailed technical descriptions of suicide methods may be easily circumvented, say the authors.