I'm not sure I understand your question.
If you are talking about the IGI that is an extraction or summary of either what is in the parish record or in a member's submission.
Each reference has a film number.
You can rent that film via your local Family History Center and look at the actual microfilm. Sometimes there is more info on the film.
The earlier the record in time, the less info is on the actual record usually.
What exactly are you looking for?