Table 4. Analysis of risk factors for clinical outcome (death) using univariate and multivariable logistic regression analyses.

Variables		Univariate analysis (a)				Multivariable analysis (b)
		OR	95% CI		P value	OR	95% CI		P value
Age		1.02	1.01	1.03	< 0.001	1.03	1.01	1.05	< 0.001
Sex		1.05	0.79	1.38	0.747
Anion gap		3.04	2.28	4.06	< 0.001	2.38	1.34	4.25	< 0.001
Creatinine		5.06	3.66	7.00	< 0.001	1.66	1.10	2.51	0.02
Field of use class	Herbicide	Reference
	Insecticide	0.2	0.12	0.32	< 0.001
	Surfactant	0.08	0	0.39	0.015
	Fungicide	0.1	0.02	0.5	0.026
Pesticide class	Bipyridylium	Reference				Reference
	Glycine Derivative	0.04	0.02	0.08	< 0.001	0.02	0.00	0.06	< 0.001
	Organophosphate	0.11	0.06	0.19	< 0.001	0.04	0.01	0.17	< 0.001
	Phosphinic acid	0.04	0.02	0.09	< 0.001	0.04	0.01	0.20	< 0.001
	Pyrethroid	0.06	0.03	0.14	< 0.001	0.01	0.00	0.09	< 0.001
	Surfactant	0.03	0.01	0.17	0.001	0.06	0.01	0.53	0.01
	Chloroacetamide	0.09	0.01	0.33	0.002	0.05	0.00	2.13	0.11
	Others	0.03	0.02	0.07	< 0.001	0.02	0.00	0.13	< 0.001
Ingested volume, mL		1	1	1	0.1556
Time lag, hr*		1.03	1	1.06	0.048
APACHE II score		1.09	1.04	1.15	< 0.001
WMSCN score		1.5	1.24	1.81	< 0.001	8.87	4.37	18.03	< 0.001
ICU admission day		0.94	0.9	0.97	< 0.001	4.23	2.98	6.02	0.001
Total admission day		0.79	0.75	0.82	< 0.001	0.22	0.16	0.31	0.001

Note that age, anion gap, serum creatinine, pesticide class, Workload Management System for Critical Care Nurses (WMSCN) score, and admission day are significant risk factors for death (P < 0.001). Both the number of patients and the death rate were incomparably higher in the herbicide (bipyridylium) category than in the other pesticide categories. Therefore, the death rates in the other pesticide groups are presented in reference to the herbicide (bipyridylium) category.

APACHE II, Acute Physiology and Chronic Health Evaluation II; ICU, intensive care unit.

^*time lag: arrival to the hospital after ingestion of pesticide.