The long-term effects of unwanted attention are coming to light

The study examines what it says is the "significant" long-term impact of stalking on its victims.

Researchers found almost 12% of the 679 men and women they surveyed in the German city of Mannheim had suffered through stalking.

The research, led by Dr Harald Dressing and in the British Journal of Psychiatry, reinforces earlier findings in Australia, the US and the UK.

"The phenomenon deserves more future community mental health research," writes Dr Dressing of Heidelberg University's Central Institute of Mental Health.

Lifestyle change

His research shows many victims of stalking suffer from anxiety, depression and sleep deprivation and have been forced to change their lifestyles.

The study indicates that stalking often puts people in genuine danger, with 24% of victims being physically restrained and nearly 20% suffering sexual assault.

Victims were predominantly female - 91 per cent - and generally experienced five different methods of intimidation, particularly nuisance telephone calls and the stalker loitering outside their home address.

Women were identified as stalkers in only 14% of cases and nearly a third had been stalked by strangers, although the majority of incidences are the product of a previous relationship.