Table 2.

Performance of the Delirium Chart Abstraction Prediction Rule

Delirium Risk	Risk Factors	Any Delirium ** n/N (%)	Incident Delirium† n/N (%)
Low	0	1/9 (11%)	1/9 (11%)
Intermediate	1–2*	13/73 (18%)	9/69 (13%)
High	3–4	9/18 (50%)	3/12 (25%)

^*One and two risk factors were combined because the delirium rate was similar in overall delirium (17–18%) and incident delirium (12–13%)

^**Chi-square = 9.2 (df=2), p=.01

^†Chi-square = 1.3 (df=2), p=.53