I'm in charge of putting together an event program, for a non-academic (business) event. We have several academics presenting, from mainland Europe and the UK.
In the agenda is it appropriate to write, for example,
- Topic Title - Dr. Firstname Lastname, Professor of xyz at XYZ University
- Topic Title - Prof. Firstname Lastname, Professor of xyz at XYZ University
- Topic Title - Prof. Dr. Firstname Lastname, Professor of xyz at XYZ University
- Topic Title - Whatever is in their linkedin profile...
(as seems to be typical on the continent)
I ask because I would like to use appropriate titles without sounding too academic and without insulting anyone. All are full professors, one emeritus. I'd like to use the same for all if possible, for consistency.
And, I am assuming that I should use at minimum a Dr. before the name even though the job title will be listed after the name, even though speakers with MBAs etc. will not have their titles listed, and will just be Firstname Lastname... not Ms. Firstname Lastname, MBA.
I would personally omit titles in such a place at all, and just list the profession, which shows clearly that they are professors:
Topic Title - John Doe, professor of nothing at University of Neverland.
If you do the same with everybody, you're fine: you can't insult people this way. I would say that the only people who really need a proper salutation always are Her Majesty and people of similar kind. With the others, it's just a matter of consistency.
Note that this may be field-dependent. As usually, in math and related field, people are more relaxed, in other field, this may be different.