Children and young people’s mental health

Looking after children’s and young people’s mental health is an urgent public health priority. Using data from the Millennium Cohort Study (MCS), CLS researchers and collaborators have investigated the prevalence of mental ill-health during childhood and adolescence, up to age 14. Their research has aimed to identify the factors associated with mental ill-health and the groups most at risk and in need of support. In addition, their studies have examined the distinction between poor mental health and poor wellbeing.

This research has received widespread public attention and achieved a variety of impacts on policy and practice.

Following on from this work, CLS researchers have explored the prevalence of mental ill-health among the cohort in their mid-teens, using MCS data, collected at age 17.

Key findings

The research

Estimating the prevalence of mental ill-health

Analysing data from the Millennium Cohort Study at age 14, the research found that a quarter of girls (24%) and one in 10 boys (9%) reported symptoms of depression. It also found that parents’ reports of their children’s mental health often differed to the children’s own reports.

These findings highlighted for the first time the extent of mental ill-health among young people, at a national level. As lead author, Dr Praveetha Patalay, said: “In recent years, there has been a growing policy focus on children’s mental health. However, until now, there has been a lack of estimates of mental health problems across the UK for this generation.”

Identifying the factors linked to poor mental health

A follow up study looked into some of the potential factors linked to poor mental health at age 14, to identify the groups most at risk.

It found that teenage girls from less well-off families were more likely to experience mental ill-health. Other factors, such as being overweight, not getting along with peers and being bullied, were also associated with high levels of depressive symptoms at age 14 for both boys and girls.

In a separate study, researchers investigated links between parental separation and young people’s mental health. The research found that the timing of the separation can make a difference to young people’s mental health. In particular, there was evidence that parental separation in late, but not early, childhood impacts negatively on adolescent mental health.

Making the distinction between mental ill-health and poor wellbeing

A study using data from the MCS Age 11 Sweep has shown that high (low) wellbeing and good (poor) mental health do not go hand in hand. Public health policy had focussed on mental health service provision, with little attention given to promoting wellbeing. These findings challenged that approach by showing that the absence of mental health difficulties was not equivalent to good wellbeing. The research also found that the factors linked to mental health difficulties and to poor wellbeing are often different.

Examining generational change

Using data from MCS and the Avon Longitudinal Study of Parents and Children, researchers compared 14-year-olds across generations, between 2005 and 2015. They found that depressive symptoms and self-harm increased over this decade, antisocial and substance use behaviours decreased, and other outcomes like obesity, insufficient sleep and poor body image increased.

The impact

Putting mental health in the spotlight

The research based on MCS age 14 data highlighted for the first time the extent of mental ill-health among young people across the UK. Through widespread dissemination in the media, it was instrumental in bringing the scale of the issue to public consciousness. Coverage included front-page headlines and follow-up features in a variety of national newspapers, and high profile interviews in the broadcast media. As NHS England’s National Mental Health Director stated to The Guardian in response to the research: ‘After decades in the shadows, children’s mental health is finally in the spotlight’.

There was also extensive coverage for the findings on changes in mental health over time, and on the links between parental break-up and children’s mental health.

Selected coverage:

The Times – Quarter of girls are depressed at 14 in mental health crisis

BBC News – Quarter of 14-year-old girls ‘have signs of depression’

BBC Analysis podcast ‘Do children of married parents do better?’

The Guardian – Poorest and brightest girls more likely to be depressed – UK study

The Telegraph – Depression and self harm on the rise among Millennials

Engaging policymakers

CLS academics, Emla Fitzsimons and Praveetha Patalay, wrote accessible briefing papers which were shared with government departments. The extensive media coverage about the research drew huge interest from policymakers, practitioners, parents, and educators. The research rapidly became part of the bloodstream of public discussion of young people’s mental health.

The researchers hosted an ESRC Festival of Social Science event, attended by policymakers and third sector, participated in the Public Health England Special Interest Group on young people’s mental health, and presented at a Conservative Party roundtable on youth mental health, and at the Public Health England (PHE) annual conference.

To help communicate the distinction between mental health and wellbeing, the researchers translated complex statistical analysis into an infographic showing risk and protective factors at age 11. This was used in several contexts and by practitioners in public health, including PHE, the Department for Education and many local government and child mental health training programmes.

Children's mental illness and wellbeing at age 11 - infographic



Click here to download the infographic as a larger version

Concrete policy impacts include decisions to increase children and young people’s (CYP) mental health services capacity and changes to PHE strategies for tackling CYP mental health. For example, due to this work, PHE has expanded its focus from one that had previously been on mental health, to also include mental wellbeing. It also adapted the framework it uses to identify how to best support young people, by extending the range of multi-level and multi-setting risk and protective factors associated with mental health and wellbeing.

This work has also framed discussion among policymakers at the Department for Education.

Read the research

Patalay, P., & Fitzsimons, E. (2016).
Correlates of Mental Illness and Wellbeing in Children: Are They the Same? Results From the UK Millennium Cohort Study
Journal of the American Academy of Child & Adolescent Psychiatry, 55(9), 771-783.
Read the full paper
Patalay P & Fitzsimons E. (2017).
Briefing – Mental ill-health among children of the new century
Centre for Longitudinal Studies: London
Read the full paper
Patalay P & Fitzsimons E. (2018).
Briefing – Mental ill-health and wellbeing at age 14
Centre for Longitudinal Studies: London
Read the full paper
Patalay, P., & Fitzsimons, E. (2018).
Development and predictors of mental ill-health and wellbeing from childhood to adolescence.
Social Psychiatry and Psychiatric Epidemiology, 53(12), 1311-1323.
Read the full paper
Patalay, P., & Gage, S. H. (2019).
Changes in millennial adolescent mental health and health-related behaviours over 10 years: a population cohort comparison study.
International Journal of Epidemiology, 48(5), 1650–1664.
Read the full paper
Fitzsimons, E., & Villadsen, A. (2019).
Father departure and children’s mental health: how does timing matter?
Social Science and Medicine, Vol. 222, 349-358.
Read the full paper

Related content


CLS researchers win impact award for mental health research

13 November 2020 Professor Emla Fitzsimons and Dr Praveetha Patalay have been awarded the 2020 ESRC Celebrating Impact Prize for their research on children and young people’s mental health.

Depression is on the rise among young people, but antisocial behaviour is down, new research shows

28 February 2019 Young people today are more likely to be depressed and to self-harm than they were 10 years ago, but antisocial behaviour and substance use – often thought to go hand-in-hand with mental ill-health – are on the decline.

Infographic – Adolescent mental health and risky behaviours

Using data from MCS and the Avon Longitudinal Study of Parents and Children, this infographic shows how adolescent mental health and risky behaviours have changed in the past 10 years.


Timing of parents’ split matters for children’s mental health, new research reveals

17 January 2019 Children who experience a family break-up in late childhood and early adolescence are more likely to have emotional and behavioural problems than those living with both parents, according to a new study.

Poor mental health is more prevalent among teenage girls from poorer backgrounds, new findings show

19 May 2018 New findings published by CLS during Mental Health Awareness Week have revealed how teenage girls from less well-off families are more likely to experience mental ill-health than their better-off peers.

One in four girls is depressed at age 14, new study reveals

29 September 2017 New research using the Millennium Cohort Study shows a quarter of girls (24%) and one in 10 boys (9%) are depressed at age 14.

Children’s mental wellbeing and ill-health: not two sides of the same coin

10 October 2016 In this blog for World Mental Health Day, Dr Praveetha Patalay examines the factors that influence children's mental illness and wellbeing using the Millennium Cohort Study.
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