The discriminator
| Feature | Delirium | Dementia | Depression |
Answer a case on the left and the matching column lights up here. Where the answer is delirium superimposed on dementia, two columns light — because both are true at once, and only one of them is the emergency.
Your bench
The golden rule. Any acute change in a person living with dementia is delirium until proven otherwise. Dementia progresses over months, not overnight — so “his dementia is getting worse” describes a timescale that does not fit what you are looking at.
“A little confused” is not an assessment. Replace it with three specifics every time: confused compared with when, confused in what domain, and can the person hold attention. Months of the year backwards takes twenty seconds and needs no form.
Ageism is a clinical error. “She is 88 and gets like this” has hidden urinary tract infections, subdural haematomas and hyponatraemias. Age is a risk factor for delirium, never an explanation for it.