Table 3.

Subgroup analyses for 28–30 days mortality excluding the study conducted by Zeiher et al.

Group	RR (95% CI)	P value	Heterogeneity (%)	P value for heterogeneity	P value for interaction test
Publication year
2005 or after	0.49 (0.16–1.52)	0.215	0.0	0.992	0.696
Before 2005	0.65 (0.27–1.59)	0.344	0.0	0.427
Mean age (years)
≥ 65.0	0.53 (0.09–2.92)	0.462	0.0	0.949	0.897
< 65.0	0.60 (0.28–1.28)	0.186	0.0	0.677
Percentage male (%)
≥ 70.0	0.63 (0.27–1.44)	0.272	0.0	0.713	0.741
< 70.0	0.48 (0.13–1.79)	0.277	0.0	0.898
Disease status
ALI	0.48 (0.20–1.15)	0.100	0.0	0.992	0.468
ALI/ARDS or ARDS	0.83 (0.25–2.71)	0.757	0.0	0.611
Baseline PaO2/FiO2 ratio
≥ 150	0.48 (0.17–1.37)	0.170	0.0	0.975	0.634
< 150	0.68 (0.26–1.77)	0.430	0.0	0.751
Jadad score
3	0.48 (0.20–1.15)	0.100	0.0	0.992	0.468
2	0.83 (0.25–2.71)	0.757	0.0	0.611

ALI Acute lung injury, ARDS acute respiratory distress syndrome, CI confidence interval, FiO ₂ fractional inspired oxygen, PaO ₂ arterial oxygen partial pressure, RR relative risk