NURSES and campaigners backed the new Herbert Protocol document.

Hannah Rogers, a dementia specialist nurse at Great Western Hospitals NHS Foundation Trust, said: “I think it’s another resource to support people. Carers are often left in the dark and don’t want to bother anybody – this is another resource to point people towards.”

Cat Medley of the Alzheimer’s Society said both carers and those with dementia found the thankfully rare occasions when the latter might go missing “incredibly stressful”.

It’s a feeling she knows all too well. Her great-uncle, whom she described as an otherwise fit and able man, went missing – taking its toll both on him and the family.

She said of the Herbert Protocol: “It’s about making sure we keep people safe.”

Det Insp Mark Kent added: “The information may need to be located quickly, at any time day or night, by a police officer to begin the initial searches. We will only ever ask for the Herbert Protocol booklet if the person is reported missing.”

Angus Macpherson, police and crime commissioner, said communities had a role in keeping an eye out for vulnerable missing people: “We’re all living longer and dementia is more of a common ailment for everyone. As we’ve heard, the amount of time Wiltshire Police spends looking for older people is increasing.”

The force estimates it spends around £4.4m a year on missing people reports. But detectives say they won't baulk at the cost of getting a helicopter up if it's needed.