Table 1 The prevalence of delirium symptom clusters at baseline

Acute change

Has there been sudden worsening in mental confusion in recent weeks or months, which has continued to the present time?

199

9.1%

Fluctuation

Are there episodes lasting days or weeks when his/her thinking seems quite clear and then becomes muddled?

264

12.0%

Are there long periods during the day when s/he is lucid and not confused (that is, knows where s/he is and knows what s/he is doing and saying)?

Does s/he get confused at night, wander about or talk nonsense?

Or at any other time? What about during the day time?

Inattention

Impaired ability to focus sustain and shift attention

230

8.7%*

Drowsiness

Disturbance of consciousness, that is either being sleepy, or awake but unaware of their surroundings

142

6.5%

Is the subject drowsy now?

Delirium judgment

Could a physical illness (not drugs or alcohol intoxication) be sufficient explanation for the subject's mental or psychiatric symptoms (e.g. delirious due to acute infection)?

34

1.6%