Sergeant1107 wrote on Sep 21^st, 2007 at 2:13am:

Lethe wrote on Sep 20th, 2007 at 9:17pm: Is it actually even correct to write "Dr. Edward Gelb, Ph.D."?  Isn't that sort of redundant, like saying "I'm Doctor Gelb and I have a doctorate"?  Does anyone know? I thought so, too. I know for medical doctors they either refer to themselves as Dr. John Doe, or as John Doe, M.D.. I don't know of anyone who refers to themselves as Dr. John Doe, Doctor.

It's quite common to list your title and your degree especially in academia where there are several degrees that confer the title "Doctor." It helps others understand which type of doctorate you hold.

Some examples:

Dr. John Doe, Ph.D., which is a terminal research degree in most disciplines
Dr. John Doe, Sc.D., also a terminal research degree equivalent to a Ph.D.
Dr. John Doe, Psy.D., which is a professional psych degree rather than a research degree
Dr. John Doe, M.D., medical doctorate, professional degree
Dr. John Doe, J.D., juris doctorate, professional degree - rarely used this way
Dr. John Doe, Pharm.D., pharmacy doctorate, professional degree
Dr. John Doe, Ed.D., education doctorate, professional degree
Dr. John Doe, D.P.H., public health doctorate, terminal research degree
Dr. John Doe, D.P.A, public administration doctorate, terminal research degree

This is not an exhaustive list...

While I agree that it is somewhat pretentious and a little bit redundant to say Dr. John Doe, Ph.D. It serve its purpose...

One other thing that I'd like to point out, in the hierarchy of academia the Ph.D./Sc.D. are the highest degree anyone can attain. M.D. and J.D. are considered professional degrees below the rank of a Ph.D.