The poor mental health of children and young people has been described as an epidemic and a "growing crisis".
The number of children needing help from child and adolescent mental health services (Camhs) in England has more than doubled in the last two years.
But it is difficult to determine to what extent this represents a real increase in the number of young people in difficulty and to what extent it is necessary to reduce the awareness of symptoms and diagnosis.
Staying in England for the moment, our best solution is to examine a representative sample of the entire population, not just those who have been dealing with mental health services.
An NHS survey of young people in England, selected from the records of the general practitioner, has just done so.
She pointed to a small but real increase in diagnosable emotional disorders, such as depression and anxiety, especially among girls.
This was based on complete psychiatric assessments of about 10,000 young people, which meant that existing problems could be solved, even if someone had never asked for help.
The researchers found that the proportion of children under 16 years old with mental disorders increased from 11.4% to 13.6% between 1999 and 2017.
This total includes things like anxiety and depression as well as behavioral disorders and hyperactivity.
"It was smaller than we thought," says Professor Tamsin Ford, a child psychiatrist and researcher.
"It's not huge, not the epidemic you're seeing reported."
The survey looked at older teenagers for the first time in 2017, suggesting that young women aged 17 to 19 are twice as likely as younger girls and twice as likely as their male counterparts have poor mental health.
There is a big gap between the increase in the number of children with mental disorders that can be diagnosed for nearly two decades and the increase in the number of references to Camhs in just two years. And this suggests that a good chunk of the increase is due to the larger number of people looking for help, not entirely to the fact that more people are in poor health.
This does not mean that all these people will get help, though.
According to national surveys conducted each year around Great Britain, the number of young people reporting mental disorders has also increased. The number of self-declared young people has increased six-fold in England, doubled in Scotland and increased by more than half in Wales in Wales between 1999 and 2014.
Again, this is despite the fact that the researchers could not find an equivalent increase in the number of people showing signs of psychological distress during a formal psychiatric evaluation.
This is probably due to the fact that children – and their parents – are better able to recognize difficulties, which leads to "reducing the gap between existing problems and reported problems," according to Professor Ford's research. .
It is also possible that some children identify painful emotions as disorders even if they are not diagnosed.
And the diagnostic methods of mental illness are not perfect either, as they try to draw a clear line [between having a condition and not] in something that is anything but clear: where ordinary anxiety feelings become an anxiety disorder, or when the feeling of unease felt by the circumstances turns into clinical depression.
Admission to the hospital
Young people are not the only ones who tend to say that they have mental health problems. In England, the number of hospitalizations for self-harm among girls has almost doubled since 1997 (although there has been no corresponding increase in boys).
An NHS Digital spokesperson said the disparity between men and women meant that the rise was unlikely to be due to an improvement in registration.
However, even with such serious symptoms, hospital records do not necessarily identify more victims.
According to Professor Ford, a better understanding by professionals has led to more cases of self-injury being recorded, whereas before, people may have been treated for their injuries without the self-inflicted nature be apprehended.
It may also be due to reduced stigma – most self-harm is hidden and the fact that more people come to the hospital does not necessarily mean there is more self-harm.
A "surprising number of people" are hurting themselves and never going to the hospital, she says.
While evidence of worsening mental health deterioration in children and young people is contradictory, according to Lorraine Khan of the Center for Mental Health, there are "some timid signs of a decline in the well-being of young women" , confirmed by the latest NHS figures. , which require an investigation.
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