"I don't know that shyness and social anxiety are discriminately different phenomena. Rather, I would suggest that social introversion can be viewed on a continuum," he says.
But because the two are so related, telling the two apart – and making the decision to treat the condition with therapy or medication, becomes difficult, says Alan Hilfer, associate director of Child Adolescent Outpatient Service at Maimonides Medical Center.
"Being able to differentiate and identify the two is the real issue and one must be careful not to over pathologize a kid who is just not sure of themselves and evidences a degree of inhibition or shyness. Many children are shy but with some encouragement or peer support they are able to find their voice. Others shrink from even the thought of a social encounter," he says.
So when should parents become worried?
"If [shy kids] are able to function, have friends do well in school and manage themselves then it doesn't necessarily warrant treatment," says Hilfer.
"When children refuse or are distressed about going to school or social gatherings ... and such distress continues over time," Merikangas says, then parents should try to inquire as the "nature of the fear" and potentially seek out some of the many websites that offer self assessment to determine if this distress is outside the realm of normal adolescent shyness."