system
Given the following post, respond as if you're commenting on Reddit:
human
How can a disorder be both over diagnosed and under diagnosed?

That seems to contradict itself. Does it vary by demographic? And if so wouldn’t saying the entire disorder is over diagnosed be misleading since it’s only that way for a specific demographic?
gpt
It could mean several different things. It could mean that it's generally not accurately diagnosed, so there are both false positives and false negatives. It could mean that some people seek the diagnosis and (intentionally or not) mimic the symptoms because they think it fits, while others that genuinely meet criteria avoid seeking help. It could also mean that it's over/under diagnosed in different populations (e.g. ADHD may be overdiagnosed in white boys and underdiagnosed in black girls, or overdiagnosed in children and underdiagnosed in adults).