Two thirds of Scottish children experience a traumatic life event such as domestic violence, neglect or parental drug misuse by the age of eight, researchers have warned.

One in ten have experienced at least three such incidents by the time they reach that age, potentially setting them up for future difficulties, the study from Edinburgh University suggests.

Researchers found boys, those from poorer families and those with young mothers were most at risk.

While an average one in ten children in Scotland had experienced one adverse event by the age of eight, this rose to one in three in the lowest income households, compared with around one in 33 in the most affluent,

There has been intense interest in Adverse Childhood Experiences (ACEs) since a ground-breaking study in California showed that the more a person experiences, the more likely they are to have problems in later life, including alcoholism, depression, heart disease, miscarriage, teenaged or unwanted pregnancies, and educational underachievement.

Research in Wales subsequently showed people who had had four or more adverse events by the time they were 18 were four times more likely to drink heavily, 15 times more likely to be a victim of violence, 16 times more likely to take drugs and 20 times more likely to go to prison.

Researchers at the University of Edinburgh looked at the incidence of seven types of adverse experience among more than 3,000 children, using data from the Growing Up in Scotland study (GUS), which tracks the lives of children from birth through their teenage years and beyond.

This is the first study to assess the scale of the problem in a current population of young people in the UK, although it looks at a narrower range of harmful experiences, and only until children are aged eight.

Even so, almost a quarter of children had experienced regular physical punishment, 10 per cent had been exposed to domestic violence and 14 per cent had been exposed to parental drug or alcohol misuse.

The most common negative experiences involved parents undergoing mental health problems or relationship break-ups, which each affected around one-third of children.

Dr Louise Marryat, Research Fellow in the Centre for Clinical Brain Sciences at the University of Edinburgh, said ACEs were known to be associated with physical and mental health problems in later life.

“This is the first study to assess the scale of the problem in a current population of young people in the UK. We hope the findings will help lead to increased support for the groups most at risk," she said.

In contradiction to other studies, boys were found to be the most likely to have suffered multiple ACEs. Dr Marryat suggested this could be explained that girls may be more likely to suffer abuse during their teenage years.

However, there is some dispute about the reliance on certain measures - such as the assumption that the break up of parents is a trauma on a par with some of the other ACEs in the study.

Marion Davis, Head of Policy at One Parent Families Scotland said one in three families with children will have been a single parent family at some point over a six-year period, she said: "We question the fact that parental separation is on the ACE list of events that could put children at risk in later life. This would mean a very significant proportion of children in the population would be included."

"Recent research debunks myths about single parents and shows there is no evidence of a negative impact of living in a single parent household on children’s wellbeing, regarding self-reported life satisfaction, quality of peer relationships, or positivity about family life, " Ms Davis added.

She added: "A focus solely on ACE’s doesn’t shine a light on the structural barriers trapping so many single parent families in poverty- expensive inflexible childcare; a benefits system which traps parents in poverty and the lack of family friendly jobs that pay the living wage".

Dr Marryat said parental or marital separation on its own was not necessarily harmful, but it could be a compounding factor. "Being in a single parent household on its own isn't necessarily harmful. The children that could be said to be a concern are those with multiple ACEs. If you are in a one parent household and there is abuse, and neglect or domestic violence then tit is possible that things would mount up."

However it is important not to take a deterministic view, and having someone to turn to also makes a difference, she said. "Research shows that even if you experience four or more ACES if you h ave a stable adult in your life, that reduces your risk greatly."

The Scottish Government says it is committed to preventing ACEs and helping reduce any effects they have on children, families and adults. It is currently consulting, with NHS Education for Scotland on a £1.35 million national training programme for those working with people who may have experienced trauma.