Stephanie Samar, a clinical psychologist at the Child Mind Institute Mood Disorders Center who did not work on the project, told Newsweek: “I am most surprised at how confident parents seemed to be about their child’s mental health and how many reported thinking that their children will talk to them about depression. Depression very often persists without diagnosis or treatment.

“Parents wait on average two years after the onset of symptoms to reach out for mental health treatment, so parents and children are most likely missing early signs of depression. Additionally, many symptoms of depression look like common pre-teen and teenage behaviors.

“For example, low energy and sleep problems are both a sign of depression as well as typical teenage behavior, especially as school demands increase,” she said.

Samar added: “People are often looking for extreme sadness when they are looking for signs of depression. In reality, irritability is a very common sign of depression in children and teens. Children can look defiant and angry when really they are struggling with depression. In addition, suicidality and self-harm are not typical teen behavior and should never be brushed aside as a phase.”