Would just like some advise, i am watching this and making notes of the people that appear in the programme some are mentioned by the narrator some have there names appear on screen the one's that are mentioned by the narrator i will mark as uncredited but what about the one's who's names appear on screen is this considered to be a credit or should they also be marked uncredited.

You're referring to names appearing on screen throughout the programme, I reckon? E.g. when someone is being interviewed the name of that person appears on screen at the beginning of the interview? I've seen that in some of my DVDs as well.

So far I have treated those as Pete suggests: treat them as regular credits, but after the end credits. The rules do not really cover the situation where there are both end credits and credits elsewhere in the programme, but not as opening credits. My line of reasoning is this: if there are no opening credits, but there are both end credits and some of these "interviewee" credits somewhere in the middle of the programme, the latter should be regarded as less "important" than the "real" end credits. Typically, the end credits might contain just a narrator or interviewer for Cast and then all the Crew credits. I think in such cases it is justified to include the "interviewee" credits after the narrator/interviewer.

The ones that are mentioned by the narrator (but not displayed on screen) could in principle be treated the same way (the rules just talk about being "credited elsewhere" - they do not stipulate in what way people should be credited). Spelling of names might however be a problem. You may need to do some research to find out how their names are spelled properly. If so, please mention your sources in your contribution notes.

This is not uncommon for documentaries to not list those being interviewed in the end credits.  I don't list them as uncredited since they are credited just not as you would normally expect in a feature film.  I credit them as they are credited in the order they are credited during the documentary.

For the verbal credit, it is still a credit but, probably safe to just list as uncredited.  If the documentary has Closed Captions or subtitles, that might help you with the spellings.

Thanks for the help