In the diagnosis of ADHD, symptoms must be present in how many settings?

In the diagnosis of Attention-Deficit/Hyperactivity Disorder (ADHD), it is essential that the symptoms be observable in two different settings. This requirement helps to ensure that the behaviors are not confined to a single environment, such as just at home or just in school, which may reflect situational or contextual issues rather than a consistent pattern of ADHD symptoms.

For example, if a child shows signs of inattention or hyperactivity in both the classroom and at home, it is more likely that these behaviors are indicative of a genuine disorder rather than simply a response to a specific setting or circumstance. The dual-setting requirement is outlined in diagnostic criteria, such as those from the DSM-5, to enhance diagnostic accuracy and to differentiate ADHD from other issues that might cause similar symptoms in particular situations.