The first comprehensive study to examine research on the mental health of children and young people using evidence from before and during COVID-19 discovered an effect on mental health that could lead to an increase in demand for support services.

The research, led by the University of Exeter and the University of Cambridge, is the first to examine research that has information on young people's mental health before and during the pandemic.

The study gives more insight into changes in the mental health of children and young people of various ages across the globe during the pandemic. The study is published in the Journal of Child Psychology and Psychiatry. 

Researchers pulled together 51 studies that looked at how the pandemic affected young people's mental health across a range of domains. Crucially, these studies included information on baseline mental health, collected before the pandemic rather than relying on retrospective perceptions of change.

The demand for fast-paced research amid the evolving pandemic meant that the standard of the studies was variable, with just four of the studies included classed as high quality.

Whilst the evidence suggested some deterioration for a few aspects of mental health, overall, the findings were mixed, with no clear pattern emerging.

There were mixed findings from studies that measured the same type of mental health difficulty in different ways, suggesting that the effects were not universal and depended on the circumstances and contexts of children, young people, and families. Researchers say the overall effect is large enough to result in an increased demand for services.

Study author Dr Tamsin Newlove-Delgado, of the University of Exeter, said: "The pandemic affected the lives of children and young people worldwide, and we've heard a lot of talk around the impact on mental health. Our review of the research in the field provides further evidence that already-stretched services are likely to see an increase in demand, but that perhaps things are not as bad for everyone as some headlines make them appear. However, even a small average change in mental health symptoms for each child can mean that, on a societal level, a large number of children tip over from managing OK to needing some professional support. Children and young people must be prioritised in pandemic recovery, and explicitly considered in planning for any future pandemic response."

The researchers found some evidence for deterioration across a range of broader measures of mental health, such as an increase in overall problems with behaviour, emotions, or anxiety, as well as finding a lot of studies that reported no change and some reporting improvements in mental health.

The paper highlights that research in this area is particularly difficult to interpret because developmentally, mental health problems became more common in adolescence than childhood.

This makes it hard to assess to what extent the negative impacts found are a result of children in the studies getting older or are actually related to the pandemic.

Co-author Professor Tamsin Ford, of the University of Cambridge, said: "Studying the whole population of children and young people means that our research may not pick up on differences between groups that may have fared better or worse during the pandemic. For example, other research has found that some children and young people reported sleeping and eating better during lockdowns, or found it easier to access remote schooling as they could work at their own pace. Others struggled with lack of structure or lack of access to remote schooling or peers."

Study author Dr Abigail Russell, of the University of Exeter, said: "The race for answers during the pandemic meant that a lot of research was conducted quickly, using opportunistic samples, for example by asking people in online surveys how they thought their child's mental health had been impacted by the pandemic. Unfortunately, that means the quality of research overall is quite poor, and even the studies that we included in our review with information from before the pandemic were overall not very high quality."

"This may be partly because of the pressure to quickly publish research about the pandemic and its impacts. As a research community, we urgently need to do better for our young people who struggle with their mental health, to understand the impact on them and their families, to target support where it's needed. In the longer term, researchers and policymakers should take a more cohesive approach to supporting and conducting high-quality research."

The study is entitled 'The impact of COVID-19 on psychopathology in children and young people worldwide: a systematic review of studies with pre- and within-pandemic data', published in the Journal of Child Psychology and Psychiatry.