None at all, what you do need is a comma (and correct spelling of dependent if this is for an essay - "large volumes of information should only be given to patients, dependent on their preference and need".
You only put in the apostrophe if there is ownership, there isn't in this case.
change dependant to depending.
no apostrophe for reasons given
comma after patients, or else it means that large vol should be given to only to patients who are depending....