From an article in The Telegraph:

Dr David Dosa, a geriatrician and assistant professor at Brown University, said that five years of records showed Oscar rarely erring, sometimes proving medical staff at the New England nursing home wrong in their predictions over which patients were close to death.

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The tortoiseshell and white cat spends its days pacing from room to room, rarely spending any time with patients except those with just hours to live.

If kept outside the room of a dying patient, Oscar will scratch on the door trying to get in.

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“It’s not like he dawdles. He’ll slip out for two minutes, grab some kibble and then he’s back at the patient’s side. It’s like he’s literally on a vigil.”