This article is from the Psychology FAQ, by Rolf Marvin Bøe Lindgren roffe@tag.uio.no with numerous contributions by others.
I am of the impression that the most commonly found diagnoses these
days are manic-depressive and borderline personality disorders
(figures are welcome).
In general, discussions of people's diagnoses are not particularly
pertinent to this newsgroup - academic psychologists, to whom this
newsgroup is dedicated, are supposed to know this.
Discussion of theories of personality disorders and/or their
treatment, on the other hand, would be appropriate.
Rather, consider why you want to know what implications a disorder
has. If it is of intellectual curiosity, the best thing would be to
read about the disorder in question. Exellent sources are
Sarason, Irwin G. & Sarason, Barbara R
(1989) Abnormal psychology: The problem of maladative behavior
6th Edition. New Jersey: Prentice Hall
Martin, Barclay
(1981) Abnormal psychology: Clinical and scientific
perspectives 2nd ed. New York: Holt, Rinehart and Winston
Unfortunately, textbooks often present clear-cut examples, and even if
they tend to warn the reader that real life is different, it's
difficult to understand just how different--and in which ways
different without actual clinical experience with the disorders in
question.
If your interest is due to an aquaintance, friend, or family member's
diagnosis, I advice against digging deeply into textbooks without
actually consulting a psychologist--at least if you plan to apply the
knowledge in any way. It's not necessary to know a lot about a
disorder in order to help somebody suffering from a problem. Knowledge
can help to steer away from pitfalls, on the other hand, it can turn a
friend into a stereotype.
Diagnoses are troublesome to begin with, and many psychologists are
wary of using diagnoses at all. It seems that the medical model of
finding the cause of a problem and then curing the problem by treating
the cause does not work with many psychological conditions.
 
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