Are there any established standards for tagging audio books and theatrical performances, like strict rules of The Scene, or internal cataloguing system of a radio station?

I want to tag my radio captures. All required information is available, such as the writer, person who translated the original writer's work, language it is currently in, actors, author of music, director of performance, person responsible for mixing the recording, etc. I am not sure how to map this information to metadata fields. It's seems even harder than with classical music. Tags themselves are freeform APEv2 or Vorbis comments, but too much freedom may result in chaos.

I am not sure where to draw analogies with tagging of music. For example, should the COMPOSER field contain the writer or the author of music. And if I'm going to add a new field called WRITER, should I deal away with 'composer' entirely and save the author of music in a completely different field.

Also, because about half of the performances will not be in English, I need a predetermined set of fields to fill out or leave empty, with descriptions where names are ambiguous.

To summarize, instead of redefining the meaning of 'composer' halfway in the tagging process, I want to adapt an existing standard. If there is any.