. Author manuscript; available in PMC: 2015 Mar 1.

Published in final edited form as: J Am Geriatr Soc. 2014 Feb 10;62(3):518–524. doi: 10.1111/jgs.12684

Table 3.

Relationship of Delirium Identification Method and Clinical Outcomes. (N=300)

		Post-operative Length of Stay^a		Post-operative Complications^a		Post-acute Facility Discharge^b

Delirium Definition	Delirium Cases	IRR 95% CI	Population Attributable Risk, %^c	IRR 95% CI	Population Attributable Risk, %	OR 95% CI	Population Attributable Risk, %
Delirium by Chart	35	1.27 (1.10-1.47)	2.50	1.94 (1.42-2.65)	5.65	14.69 (3.78-57.03)	4.91
Delirium by CAM	68	1.17 (1.04-1.31)	3.23	1.50 (1.13-1.99)	7.56	4.78 (2.22-10.33)	7.82
Combined Delirium	82	1.18 (1.06-1.32)	4.16	1.53 (1.17-2.01)	9.49	6.16 (2.95-12.84)	10.74

Note: Adjusted for age, female sex, nonwhite race, surgical type, pre-operative Charlson comorbidity index, pre-operative proxy Informant Questionnaire of Cognitive Decline in the Elderly (IQCODE), and post-operative Acute Physiology and Chronic Health Evaluation II (APACHE II) score;

Poisson Model

Logistic Regression Model;

Population attributable risk percentage is the product of a function of the relative risk (RR) of the outcome among those with delirium ([RR – 1])/RR) and the prevalence of delirium.

IRR = Incident rate ratio; 95% CI = 95% Confidence Interval; OR = Odds Ratio; CAM = Confusion Assessment Method