Jon. said:
He said basically, no, there isn't, but intelligent people might be diagnosed more readily because they are more likely to be in jobs that require high mental functioning. If the local garbage collector started to get depressed and his higher mental functions were impaired, it's not likely that it would affect his work to the point where he needed to seek help. If it's a doctor, an accountant, or a lawyer, for example, that person is more likely to notice it (and/or have it noticed by others).