Canterbury District Health Board is to apologise again to the family of a man who died after being sent home from Christchurch Hospital in April last year.
Dean Carroll, 25, died from an undiagnosed spinal infection after being treated at the hospital's emergency department for back pain.
A report by the Health and Disability Commissioner says the health board failed to provide Mr Carroll with services of an appropriate standard because the emergency department lacked adequate resources.
The report calls for a further review of the hospital's emergency department, and recommends the board apologise in writing to Mr Carroll's parents and his partner.
The board says it has increased the number of beds and staff in the department since Mr Carroll's death.
Patient safety at risk - commissioner
Health and Disability Commissioner Ron Paterson says patient safety is at risk in over-crowded hospital emergency departments.
Mr Paterson has released five reports into separate investigations by his office, one of them relating to the care given to Mr Carroll, who died of acute blood poisioning a day after being discharged.
Mr Paterson says there have been improvements, but it took time to get action.
Mr Paterson says problems are not confined to Canterbury and a national effort is needed to tackle emergency department overcrowding.
The heavy workload faced by emergency department doctors was a mitigating factor in cases he investigated, he said.
The other cases released on Tuesday stress the need for providing good information for patients and families at discharge, good handover notes between clinical staff, and efficient systems for reviewing test results.
But Mr Carroll's father says he has no confidence that Mr Patterson's recommendations will be followed.
Dave Carroll says he does not want the same thing to happen to someone else.