More schoolgirls face emotional problems now than they did five years ago, according to a new English study published in the Journal of Adolescent Health.
The research carried out by the Evidence Based Practice Unit (EBPU), a collaboration between University of College London and the Anna Freud Centre, found emotional problems in girls aged 11-13 had increased by 55 per cent between 2009 and 2014.
The findings mean that in a mixed classroom of 30 children today it is likely to contain one more girl with emotional difficulties than a comparable class five years ago.
Researchers say the numbers of adolescents in England experiencing other mental health difficulties had not changed significantly making the rise in emotional problems particularly striking.
Lead author Dr Elian Fink from the EBPU said: "Five years is a relatively short period of time, so we were suprised to see such a sharp spike in emotional problems among girls. The fact that other mental health issues stayed about the same makes us think that there must have been significant changes over the past five years which have specifically affected young girls.
"Whatever is causing the rise of emotional problems, it is clear that we need more effective interventions. These might include encouraging teachers to look out for emotional problems in young girls and increasing provision of youth mental health services."
The study compared the mental health of 1,638 schoolchildren in 2009 with a demographically-matched sample of the same number of pupils from 2014. The pupils, all in school years 7 and 8, were matched by age, gender, ethnicity and the overall socio-economic mix of their schoools.
Co-author Dr Helen Sharpe said the data examined contained more children from ethnic minority backgrounds than the national average and as such was not representative of England as a whole.
"However,our data did not show significant differences in emotional problems between children from different ethnic backgrounds. As a result, I think we can be confident that the increase we saw would apply across the board despite the unrepresentative sample."
Dr Miranda Wolpert, director of the EBPU, said contributory factors for the rise in emotional problems among girls could include increased academic pressure as well an increased sexualisation and objectification of girls and young women which had been amplified by social media.
Read the article in the Journal of Adolescent Health here