Is there any particular information that should be included in or left out of a cv when applying for a PhD position? Should it be kept to a minimum with only relevant work experience included for example?

You CV should list your qualifications and include the title of any research projects you have undertaken as part of your degree or otherwise. Like any other CV you should list your previous and current employment (if applicable). In addition it should contain the names of at least 2 academic referees. If you wish to include a previous employer as a referee, make this in addition to the academic referees (unless you have no other option).