Table 2.

Univariable Logistic Regression Analysis of Variables Associated with the Length of On-Site Time.

Variables	Odds Ratio	95% confidence interval			p-Value
Age groups: years
19-59			Reference
60-69	0.98	0.95	to	1.01	0.23
70-79	0.92	0.90	to	1.91	<0.001
80-89	0.88	0.85	to	0.90	<0.001
89 <	0.80	0.76	to	0.83	< 0.001
Sex
Male	1.18	1.16	to	1.21	< 0.001
Year
2004-2007			Reference
2008-2010	1.17	1.11	to	1.23	< 0.001
2011-2013	1.26	1.21	to	1.32	< 0.001
2014-2016	1.49	1.43	to	1.56	< 0.001
2017-2019	1.53	1.46	to	1.60	< 0.001
Month
January-March			Reference
April-June	0.89	0.86	to	0.91	< 0.001
July-September	0.85	0.83	to	0.99	< 0.001
October-December	0.91	0.88	to	0.93	< 0.001
Days of the week
Weekdays			Reference
Weekends/Holidays	1.08	1.06	to	1.10	< 0.001
Time
Daytime	0.75	0.74	to	0.77	< 0.001
Alcohol consumption
Yes	1.44	1.39	to	1.49	< 0.001
Type of trauma
Traffic accident			Reference
Fall	1.06	1.03	to	1.08	< 0.001
Other blunt trauma	1.09	1.04	to	1.13	< 0.001
Penetrating trauma	1.16	1.09	to	1.22	< 0.001
Cause of trauma
Accident			Reference
Occupational injury	0.96	0.92	to	1.00	0.08
Suicide	0.91	0.87	to	0.95	< 0.001
Violence	1.45	1.33	to	1.58	< 0.001
Unclassified/rare mechanisms	1.21	1.08	to	1.34	0.001
Prehospital vital signs
Hypotension (< 90 mmHg)	0.96	0.92	to	1.01	0.09
Severity of trauma
Revised trauma score	1.20	1.19	to	1.21	< 0.001
AIS
AIS1 > 3	0.75	0.74	to	0.77	< 0.001
AIS2 > 3	0.76	0.67	to	0.85	<0.001
AIS3 > 3	0.74	0.64	to	0.85	<0.001
AIS4 > 3	0.78	0.76	to	0.79	< 0.001
AIS5 > 3	0.80	0.77	to	0.84	< 0.001
AIS6 > 3	1.40	1.35	to	1.45	< 0.001
AIS7 > 3	1.15	1.10	to	1.21	< 0.001
AIS8 > 3	0.78	0.76	to	0.79	< 0.001
AIS9 > 3	0.74	0.48	to	1.17	0.20
Interventions before hospital arrival
Oxygen	0.89	0.87	to	0.91	< 0.001
Immobilization	1.10	1.08	to	1.12	< 0.001
Chest compression	0.33	0.32	to	0.35	<0.001
Intravenous line placement	0.79	0.73	to	0.85	< 0.001
Defibrillation	0.47	0.37	to	0.60	<0.001
Intubation	0.59	0.52	to	0.66	< 0.001
Comorbidities
Mental disease	1.07	1.02	to	1.11	0.001
Chronic kidney disease on hemodialysis	1.10	1.01	to	1.19	0.04
Malignancy	1.12	1.05	to	1.19	0.001
Diabetes mellitus	1.08	1.05	to	1.12	<0.001
Ischemic heart disease	1.02	0.97	to	1.08	0.38
Chronic heart disease	0.93	0.87	to	1.00	0.06
Cerebrovascular disease	1.01	0.97	to	1.06	0.66
Dementia/mental retardation	0.90	0.86	to	0.94	<0.001

AIS: abbreviated injury scale.