I have not been able to find an existing question similar to mine, but apologies if I've missed one.
I write an academic dissertation where I mention a lot of people. The first time someone is mentioned, I present him or her with an apposition, usually a title or affiliation, e.g. the physicist Jessica Ronan and the engineer Patrick Boyd. Now suppose that Ronan is mentioned very frequently, while Boyd is only mentioned now and then. Is it considered good practice to avoid repeating the affiliation for Ronan but occasionally repeat it for Boyd?
My intuition is that readers would never lose track of who Ronan is, and therefore always remember her as the physicist. With Boyd, who is only mentioned at every 20-30 pages or so, perhaps the readers need a little reminder at some point. Or is it a good idea to do that also for Ronan?
Don't forget these are not the only two persons in the text, there is about 100 all in all.
I should also add that I have a name index at the back of the book. Does this entirely remove the need for repetitions of the form above?
Here's an example of a historian that has done something similar (before this quoted passage, Copernicus has already been presented):
Copernicus’s theory remained incomplete, but the German physicist Johannes Kepler (1571--1630) was able to provide mathematical evidence in its support, while the Pisan astronomer Galileo Galilei (1564--1642) tested the Copernican hypothesis empirically by observing the planets through the telescope, which he had himself perfected.
Taken from page 67 in this book Karen Armstrong "The Battle for God".
Notice that this historian not only mentioned the profession of the persons but also their nationality and birth and death years.