Table 2.

Characteristics of randomized, controlled trials included in the meta-analysis.

	Age		Gender (male/female)		Vt (ml/kg)		PEEP (cmH2O)		Number		Pulmonary complication ( N )
	P group	C group	P group	C group	P group	C group	P group	C group	P group	C group	P group	C group
1	59.0 ± 9.0	55.0 ± 12.0	9/22	13/18	7	10	10		31	31	10	11
2	51.1 ± 8.9	50.3 ± 9.8	/	/	7	9	30		44	43	4	11
3	/	/	/	/	6–8	8–10	6		35	35	0	7
4	69.7 ± 5.8	70.8 ± 5.8	98/42	102/38	6	10	5		130	130	24	41
5	52.8 ± 16.5	57.4 ± 10.1	14/7	9/10	6	10	5		21	19	3	9
6	63.8 ± 9.7	68.2 ± 8.3	18/14	15/9	7	9	5		32	28	2	4
7	69.9 ± 6.3	68.6 ± 4.0	11/9	12/8	6	6	7	12	22	22	1	4
8	64.0 ± 6.0	62.0 ± 4.0	23/22	26/19	8	8	5		45	45	3	11
9	70.7 ± 7.1	71.1 ± 6.7	10/13	20/16	6–8	8–10	8–10		36	36	1	7
10	70.6 ± 9.3	70.2 ± 9.4	40/22	39/23	7	8–10	5		62	62	9	21
11	69.3 ± 3.0	70.2 ± 4.3	22/18	25/15	6	10	6		40	40	2	5
12	66.5 ± 8.3	66.1 ± 9.2	35/23	34/23	7	10	7		58	57	1	8
13	55.4 ± 10.7	56.0 ± 12.9	17/18	18/12	6–8	6–8	2		35	30	2	4
14	47.8 ± 12.0	50.0 ± 10.0	12/8	14/6	6	10	5		20	20	2	7
15	51.3 ± 10.3	54.4 ± 6.8	/	/	7	9	7		30	30	0	4
16	43.2 ± 7.3	43.2 ± 7.3	/	/	6	10	8–10		45	45	1	5
17	/	/	/	/	6	10	8–10		30	30	3	8
18	53.3 ± 7.3	52.5 ± 7.0	36/13	32/17	6	9	5		49	49	9	15
19	57.6 ± 5.0	56.9 ± 5.2	12/8	10/10	6	6	5		20	20	1	2
20	68.4 ± 4.0	69.1 ± 4.7	16/14	13/17	6	8	5		30	30	2	3
21	56.2 ± 4.3	57.5 ± 4.8	25/15	21/19	6–8	6–8	10	5	40	40	5	6
22	63.0 ± 6.0	63.0 ± 8.0	56/24	52/28	6	9	5		80	80	14	25
23	1.5 ± 0.5	1.7 ± 0.3	12/8	11/9	7	10	6		20	20	1	2