'Hospitals should employ safety experts', says victim's husband
24 June 2014 Last updated at 22:50 BST
A fifth of hospital trusts in England may be covering up mistakes, a government review suggests.
The analysis of reporting incidents shows 29 out of 141 trusts were not registering the expected number of safety incidents. The review said this may be a sign of a "poor" safety culture.
Health Secretary Jeremy Hunt said it was important hospitals were "open and honest", and that patients had a right to know about problems with reporting.
Martin Bromiley, whose wife died in 2005 following a minor operation in hospital, told the BBC that understanding why organisations were not reporting incidents was key.