Helen Maree Dale Wilkins, 85 disappeared from a dementia care facility in 2017 has now been declared dead by the coroner in a report which blames staff at the rest home facility for the length of time before she was discovered missing.

Wilkins disappeared from Leigh Road Cottage between 5.30pm on November 7, 2017, when she was last seen in the garden and when a staff member noticed she was missing at 6.45am the next day.

Staff assumed Wilkins had taken herself to bed as she often did. The evening staff nor those who came on shift at 10.45pm opened her door to check on her because she was known to wake when the door was opened.

At 5am staff discovered she was not in her room but assumed she had gone to breakfast even though it appeared that the bed had not been slept in, the coroner's report noted.

About 6.45am a staff member noticed Wilkins was not at breakfast and staff searched the building and the grounds but did not find her. The facility manager and police were informed.

Police and Search and Rescue searched both land and sea around the area but found no sign of the 85-year-old before the search was called off at the end of November 2017.

In her just-released findings, Coroner Debra Bell has concluded Wilkins died. The coroner said she could not rule her death a suicide because there was no evidence she intended to end her life that day.

"It remains a possibility that she left the facility and became confused and unable to return," said Bell.

A report provided to Waitemata District Health Board by Leigh Road Cottage found staff did not follow company procedure by checking on residents at 1am and 3am as well as 5am. Staff were also not sure if she was inside when the facility was locked at 7pm.

The report found that as there were no cameras on site, so how and where Wilkins managed to escape was unable to be determined.

It was also revealed there had been other instances of residents escaping which had not been reported to the DHB. In one of those, a man was missing for six hours when he was let out by a visitor.

Leigh Road Cottage has since instigated protocols that require staff to physically check on residents hourly between 7pm and 6am, and sign a daily checking record.

Double locks were placed on the back gate, a new gate was installed at the front of the facility and a camera was also installed.

Given all the changes made, Bell had no further recommendations to make.

"I do record that Leigh Road Cottage staff's failure to follow correct processes on the night of Mrs Wilkins disappearance contributed to the length of time it took to determine that she was missing. Additionally, there was the reasonable expectation that the facility was secure and Mrs Wilkins would not be able to leave as she did," Bell summed up.

"I note the DHB is satisfied with the changes made by Leigh Road Cottage. I am hopeful that these changes will reduce the chances of further deaths occurring in similar circumstances as Mrs Wilkins."

A Waitematā DHB spokeswoman said the organisation fully supported the coroner's findings.