The Royal Society of Medicine, London, is holding a conference: Big Health Data: improving patient care, on 5 June 2014. If this subject interests you, have a look at the link and consider attending. There will be interesting presentations and discussion, (hopefully mine on dark data, too).
https://www.rsm.ac.uk/events/events-listing/2013-2014/sections/telemedicine-ehealth-section/tee04-big-health-data-improving-patient-care.aspx