Table 2.

Univariate meta-regression of possible sources of heterogeneity across the included studies.

Heterogeneity factors	Co-efficient (95% CI)	P-value
Mean age	1.00 (0.92, 1.10)	0.93
Male (%)	0.99 (0.98, 1.00)	0.15
Location
Asia	Reference
USA	0.72 (0.26, 1.94)	0.51
Europe	1.00 (0.42, 2.42)	1.00
Level of care
Intensive care only vs. all hospitalization (reference)	0.85 (0.35, 2.03)	0.71
Hypertension (%)	0.99 (0.97, 1.01)	0.42
Diabetes (%)	0.99 (0.96, 1.01)	0.20
Chronic kidney disease (%)	0.97 (0.90, 1.05)	0.43
Sample size
< 1000	Reference
≥ 1000	0.61 (0.29, 1.29)	0.20