Table 1.

Summary of variables in the trauma dataset relevant to this work, n= 5,693.

	Frequency	Mean (SD)	Frequency (%)
Variable	missing (%)	in observed data	in observed data
Massive transfusion (outcome)	0 (0)		518 (9)
Age (years)	0 (0)	40 (20)
Sex: male	0 (0)		4161 (73)
Injury type: penetrating	23 (0.4)		580 (10)
Time to emergency dept. (mins)	2396 (42)	65 (40)
Systolic blood pressure (mm Hg)	425 (7)	126 (29)
Base deficit (mM)	868 (16)	3.4 (5.1)
Prothrombin time (seconds)	1,648 (29)	17 (8)

SD, standard deviation.