Posting anonymously about my girl friend, who is a nurse at a major London hospital, whose experiences echo the previous anonymous nurse's post.
Indeed, all patient information is already entered on a computer system (local to the hospital, I believe). Computer security is bypassed on an almost continuous basis due to factors such as agency staff (of which there are enormous numbers) without their own logins (or trackable guest logins), borrowed logins due to forgotten passwords or delayed userid/password setup, or simply because the system security is so horrible to use that they haven't got time or can't be bothered - if you make something too difficult for people to use then they won't; if it's security then they'll bypass it.
Now almost every dept in the NHS probably has at least one agency staffer. So how easy do you think it is for an unscrupulous person to get a job with access to confidential data? And what do you think the chances of tracing that person would be, given the above situation? If they used a fake ID (perhaps built from the handy data on that copy of that nice HMRC CD they bought from ebay or downloaded!)
Also, physical security is similarly lax, for much the same reasons: security doors that should be accessible only by ID swipe badge are wedged open, again for reasons such as agency staff haven't got the access badges, locks faulty (for weeks at a time), or can't be bothered with them. On the one occasion I visited the dept to meet my girl-friend after work, I was able to walk through the wedged open security doors into the "secure" area, and was able to wait in the empty managers office, where I had immediate physical access to the PC and hospital network and systems (the manager being busy helping out with clinical matters due to the chronic staff shortages).