Table 3.

Subgroup analysis of inflammatory related factors and incidence of ARDS/ALI

Inflammatory factors	Groups	No. of studies	SMD	95%CI	P value	Heterogeneity (%)	P for heterogeneity
ANG‑2	Sample size
	≥ 100	5	1.30	0.47 to 2.13	0.002	97.8	< 0.001
	< 100	1	1.59	0.97 to 2.20	< 0.001	–	–
	Mean age (years)
	≥ 60.0	3	1.74	1.30 to 2.18	< 0.001	51.1	0.129
	< 60.0	3	0.98	−0.02 to 1.98	0.055	98.4	< 0.001
	Patients’ status
	ARDS	1	2.15	1.65 to 2.64	< 0.001	–	–
	ALI	3	1.38	−0.19 to 2.93	0.085	98.3	< 0.001
	ARDS/ALI	2	0.91	−0.34 to 2.16	0.152	93.7	< 0.001
	Specimen source
	Blood	6	1.34	0.59 to 2.10	< 0.001	97.4	< 0.001
	BALF	0	–	–	–	–	–
IL-1β	Sample size
	≥ 100	2	−0.33	−1.05 to 0.40	0.379	79.7	0.026
	< 100	8	1.26	0.48 to 2.04	0.002	89.9	< 0.001
	Mean age (years)
	≥ 60.0	1	−0.75	−1.34 to −0.15	0.014	–	–
	< 60.0	7	1.33	0.43 to 2.23	0.004	94.4	< 0.001
	Patients’ status
	ARDS	6	1.39	0.41 to 2.37	0.005	91.8	< 0.001
	ALI	4	0.22	−0.59 to 1.04	0.590	88.0	< 0.001
	Specimen source
	Blood	5	1.39	0.15 to 2.62	0.028	95.3	< 0.001
	BALF	6	0.73	−0.19 to 1.66	0.121	90.2	< 0.001
IL‑6	Sample size
	≥ 100	5	0.45	−0.26 to 1.16	0.215	96.1	< 0.001
	< 100	8	0.83	0.11 to 1.55	0.024	91.6	< 0.001
	Mean age (years)
	≥ 60.0	3	1.49	0.37 to 2.61	0.009	92.1	< 0.001
	< 60.0	10	0.43	−0.06 to 0.92	0.088	93.1	< 0.001
	Patients’ status
	ARDS	7	0.80	0.03 to 1.57	0.043	92.6	< 0.001
	ALI	6	0.54	−0.12 to 1.20	0.108	95.3	< 0.001
	Specimen source
	Blood	11	0.37	−0.04 to 0.77	0.074	88.8	< 0.001
	BALF	7	1.33	0.24 to 2.42	0.016	93.2	< 0.001
IL‑8	Sample size
	≥ 100	4	0.06	−1.84 to 1.95	0.953	99.2	< 0.001
	< 100	10	0.74	0.15 to 1.33	0.014	87.7	< 0.001
	Mean age (years)
	≥ 60.0	2	2.87	−1.95 to 7.70	0.243	96.6	< 0.001
	< 60.0	9	0.52	−0.61 to 1.65	0.364	98.5	< 0.001
	Patients’ status
	ARDS	6	1.28	0.34 to 2.21	0.007	90.4	< 0.001
	ALI	7	0.13	−1.13 to 1.40	0.834	98.6	< 0.001
	ARDS/ALI	1	−0.37	−0.93 to 0.20	0.201	–	–
	Specimen source
	Blood	9	0.67	−0.50 to 1.85	0.262	98.3	< 0.001
	BALF	8	0.78	0.08 to 1.48	0.029	86.1	< 0.001
IL-10	Sample size
	≥ 100	2	−0.90	−7.01 to 5.21	0.772	99.6	< 0.001
	< 100	5	1.89	0.59 to 3.19	0.004	93.4	< 0.001
	Mean age (years)
	≥ 60.0	0	–	–	–	–	–
	< 60.0	6	1.29	−0.75 to 3.32	0.216	98.6	< 0.001
	Patients’ status
	ARDS	3	1.62	0.05 to 3.19	0.043	91.7	< 0.001
	ALI	4	0.73	−2.15 to 3.61	0.618	99.0	< 0.001
	Specimen source
	Blood	4	0.18	−2.64 to 3.00	0.899	99.0	< 0.001
	BALF	4	1.90	0.12 to 3.68	0.037	94.3	< 0.001
PAI‑1	Sample size
	≥ 100	3	0.42	−0.78 to 1.61	0.497	98.8	< 0.001
	< 100	4	0.89	0.52 to 1.27	< 0.001	42.1	0.159
	Mean age (years)
	≥ 60.0	1	0.31	−0.35 to 0.96	0.363	–	–
	< 60.0	6	0.77	−0.04 to 1.57	0.063	97.6	< 0.001
	Patients’ status
	ARDS	2	0.68	0.06 to 1.29	0.030	61.1	0.109
	ALI	4	0.77	−0.54 to 2.08	0.250	98.1	< 0.001
	ARDS/ALI	1	0.66	0.45 to 0.87	< 0.001	–	–
	Specimen source
	Blood	6	0.44	−0.34 to 1.22	0.267	97.2	< 0.001
	BALF	3	1.57	0.77 to 2.36	< 0.001	69.6	0.037
TNF‑α	Sample size
	≥ 100	4	1.66	−0.10 to 3.43	0.065	98.3	< 0.001
	< 100	12	0.76	0.27 to 1.24	0.002	85.5	< 0.001
	Mean age (years)
	≥ 60.0	3	0.51	0.17 to 0.84	0.003	0.0	0.482
	< 60.0	10	1.36	0.52 to 2.20	0.002	96.0	< 0.001
	Patients’ status
	ARDS	9	1.05	0.11 to 1.99	0.028	94.7	< 0.001
	ALI	5	0.90	−0.14 to 1.95	0.090	95.1	< 0.001
	ARDS/ALI	2	0.92	−0.14 to 1.97	0.089	86.5	0.007
	Specimen source
	Blood	9	1.00	0.12 to 1.89	0.026	95.7	< 0.001
	BALF	10	0.91	0.26 to 1.57	0.006	87.6	< 0.001