Table 1. Summary of the selected studies for meta-analysis^19-21.

Author, year	Study design	Subject	Main finding	Reference
Zeeshan et al., 2019	Multicenter, retrospective	468 patients w/o preinjury anticoagulants.	Compared to FFP alone, addition of 4-PCC contributed to decreased mortality (17.5% vs. 27.7%, p = 0.01), lower rates of acute respiratory distress syndrome (1.3% vs. 4.7%, p = 0.04), and incidence of acute kidney injury (2.1% vs. 7.3%, p = 0.01).	19
Jehan et al., 2018	Unicenter, retrospective	120 patients w/o preinjury anticoagulants	4-PCC + FFP was associated with an accelerated correction of INR (373 vs. 955 mins; p = 0.001), decreased need of transfusion, and lower mortality.	20
Joseph et al., 2014	Unicenter, retrospective	252 patients escorted to trauma center and with initial INR ≥ 1.5	Extra PCC with baseline FFP facilitated INR normalization, reduced pRBC or FFP supplementation, and declined mortality.	21