Table 2.

The association between prehospital fluid resuscitation and outcomes in the original cohort, propensity-matched cohort, and IPTW cohort.

	Prehospital fluid resuscitation on the ambulance
	Yes (n = 4318)	No (n = 27,417)	aOR (95% CI)*	p
Outcome of the original cohort (n = 31,735)
In-hospital mortality
Yes, n (%)	124 (2.9)	147 (0.54)	2.89 (1.92–4.34)	< 0.001
No, n (%)	4194 (97.1)	27,270 (99.46)
Functional outcome
Poor, n (%)	722 (16.7)	1849 (6.7)	1.92 (1.64–2.25)	< 0.001
Favoriable, n (%)	3596 (83.3)	25,568 (93.3)

Prehospital fluid resuscitation on the ambulance
	Yes (n = 3024))	No (n = 3024)	OR (95% CI)	p
Outcome of the propensity-matched cohort (n = 6048)
In-hospital mortality
Yes, n (%)	64 (2.1)	32 (1.1)	2.02 (1.32–3.10)	0.001
No, n (%)	2960 (97.9)	2992 (98.9)
Functional outcome
Poor, n (%)	463 (15.3)	286 (9.5)	1.73 (1.48–2.03)	< 0.001
Favoriable, n (%)	2561 (84.7)	2738 (90.5)

	Prehospital fluid resuscitation on the ambulance
	Yes (n = 8213.2)	No (n = 30,777.7)	OR (95% CI)	p
Outcome of the IPTW cohort (n = 38,990.9)#
In-hospital mortality
Yes, %	2.5	0.6	4.26 (3.50–5.20)	< 0.001
No, %	97.5	99.4
Functional outcome
Poor, %	15.2	7.1	2.33 (2.16–2.51)	< 0.001
Favorable, %	84.8	92.9

IPTW inverse probability of treatment weighting, CI  confidence interval, OR  odds ratio, aOR adjusted odds ratio.

*Adjusted for age, sex, country, mechanism of injury, location of injury, diagnosis of injury, injury severity score, major trauma, shock, SBP, DBP, HR, and RR on the ambulance.

^#The extreme weights were truncated at the 97th percentile.