Editorial Perspective: Why I am now convinced that emotional disorders are increasingly common among young people in...

This editorial perspective comments on the evidence that mental health is deteriorating among children and young people at the same time as the impact of poor mental health is more impairing. It discusses the methodological difficulties in detecting a 'true' change in prevalence. There are particular gaps in the evidence from low- and middle-income countries and also in relation to autism spectrum disorders. The evidence in high-income countries points to recent increases in anxiety, depression and self-harm in teenagers, particularly young women. We need more longitudinal data to disentangle the potential explanations for these changes.