For accurate diagnosis, a child must display some of the aforementioned symptoms for at least 2 weeks. These symptoms must be a distinct shift from previous behavior. A clinician will also need to rule out other causes for these symptoms, including substance abuse, medical conditions like diabetes and hypothyroidism, and other psychiatric disorders. The condition must significantly interfere with day-to-day activities.
The symptoms of depression in children vary, making it more difficult to properly diagnose. It is often undiagnosed and untreated because they are passed off as normal emotional and psychological changes that occur during growth. According to the National Institute for Mental Health, early medical studies focused on “masked” depression, where a child’s depressed mood was evidenced by acting out or angry behavior. While this does occur, particularly in younger children, many children display sadness or low mood similar to adults who are depressed.