Kent hospitals: Serious untoward incidents (SUIs) revealed
Nearly 400 "serious untoward incidents" (SUIs) were reported in Kent's hospitals in the last financial year, a BBC investigation has discovered.
Cases include operations on the wrong part of the body, the wrong diagnosis given to patients, foreign objects left behind after surgery, and deaths.
Darent Valley Hospital had the most recorded SUIs, with 120. The Maidstone and Tunbridge Wells NHS Trust had 117.
NHS England said the vast majority of patients received harm-free care.
Following a Freedom of Information request, BBC Radio Kent discovered there were 397 SUIs during 2014-15, of which six were "never events" - serious, largely preventable incidents which should never happen.
There were 86 SUIs at East Kent Hospitals University NHS Foundation Trust, and 68 at the Medway Maritime Hospital, which had four "never events".
The Medway Foundation Trust said it had recently introduced "a raft of new measures" to help improve the way it investigated serious incidents on behalf of patients and their families.
Dartford and Gravesham NHS Trust, which runs Darent Valley Hospital, said it was "exceedingly vigilant and confident" in reporting any instances where it felt the delivery of care had been below standard.
Maidstone and Tunbridge Wells NHS Trust said it held "thorough investigations" into all SUIs, while East Kent Hospitals NHS Trust said it had "robust policies in place to fully investigate and implement learning from each serious incident to prevent it from occurring again".
Joyce Robins, from Patient Concern, said: "Mistakes are preventable if you take sufficient care.
"I don't like the fact that they are steadily rising, when I would have hoped with modern methods, and modern training, they would be going down."
Analysis: BBC South East health correspondent Mark Norman
"Never events" include surgery on the wrong bit of the body, leaving instruments inside patients or giving people the wrong chemotherapy drugs.
Sadly, they do happen, and between April and September last year, 102 NHS trusts had at least one "never event".
It is worth putting these figures into context.
There were 15.89m total hospital admissions in 2014-15 - 31% more than a decade earlier.
The NHS in England is also one of few healthcare systems in the world that is this open and transparent about patient safety and incident reporting, particularly around "never events".
We may not like what is happening at times but at least we have the information and can call hospitals to account.
Hopefully we'll get to a point where "never events" never happen.