Preventive effect of probiotics on infections following colorectal cancer surgery: An umbrella meta-analysis

Table 2 Overall and stratified analyses for the impacts of probiotics on post-surgical infections in patients undergoing colorectal cancer surgery

		Subgroups	Studies	Relative risk (95%CI)	I2 (%)	P value	Publication bias
Total infections		Overall	6	0.40 (0.31-0.51)	56.1	0.04	0.31
	Supplementation type	Multi-strain Probiotics	3	0.50 (0.41-0.61)	0.0	0.39
		Multi-strain Probiotics and synbiotics	3	0.31 (0.25-0.40)	0.0	0.56
	Intervention time	Preoperative	4	0.31 (0.25-0.40)	0.0	0.77
		Pre- and postoperative	2	0.52 (0.42-0.64)	0.0	0.85
	Country	China	4	0.37 (0.26-0.52)	59.6	0.06
		Other countries	2	0.44 (0.29-0.68)	59.7	0.11
	Quality of studies	High	3	0.31 (0.25-0.40)	0.0	0.56
		Moderate	3	0.50 (0.41-0.61)	0.0	0.39
Urinary tract infections		Overall	5	0.44 (0.31-0.61)	0.0	0.66	0.009
	Supplementation type	Multi-strain Probiotics	3	0.43 (0.27-0.69)	16.2	0.30
		Multi-strain Probiotics and synbiotics	2	0.44 (0.26-0.74)	0.0	0.86
	Intervention time	Preoperative	3	0.38 (0.25-0.59)	0.0	0.57
		Pre- and postoperative	2	0.52 (0.32-0.86)	0.0	0.49
	Country	China	3	0.43 (0.27-0.59)	16.4	0.30
		Other countries	2	0.45 (0.27-0.75)	0.0	0.89
	Quality of studies	High	2	0.44 (0.26-0.74)	0.0	0.86
		Moderate	3	0.43 (0.27-0.69)	16.2	0.30
Bacteremia		Overall	3	0.41 (0.30-0.56)	0.0	0.91	0.80
	Supplementation type	Multi-strain Probiotics	1	0.40 (0.26-0.62)	-	-
		Multi-strain Probiotics and synbiotics	2	0.42 (0.27-0.67)	0.0	0.70
	Intervention time	Preoperative	2	0.42 (0.27-0.67)	0.0	0.70
		Pre- and postoperative	1	0.40 (0.26-0.62)	-	-
	Country	China	1	0.37 (0.16-0.86)	-	-
		Other countries		0.42 (0.30-0.59)	0.0	0.74
	Quality of studies	High	2	0.42 (0.27-0.67)	0.0	0.70
		Moderate	1	0.40 (0.26-0.62)	-	-
Sepsis		Overall	5	0.35 (0.25-0.44)	0.0	0.90	0.87
	Supplementation type	Multi-strain Probiotics	1	0.28 (0.17-0.47)	-	-
		Multi-strain Probiotics and synbiotics	4	0.35 (0.25-0.50)	0.0	0.92
	Intervention time	Preoperative	4	0.31 (0.23-0.43)	0.0	0.92
		Pre- and postoperative	1	0.41 (0.22-0.78)	-	-
	Country	China	3	0.31 (0.21-0.46)	0.0	0.78
		Other countries	2	0.35 (0.23-0.53)	0.0	0.52
	Quality of studies	High	4	0.35 (0.25-0.50)	0.0	0.92
		Moderate	1	0.28 (0.17-0.47)	-	-
Surgical site infection		Overall	10	0.56 (0.49-0.63)	0.0	0.71	0.94
	Supplementation type	Multi-strain Probiotics	5	0.56 (0.45-0.70)	0.0	0.70
		Multi-strain Probiotics and synbiotics	5	0.56 (0.47-0.66)	5.8	0.37
	Intervention time	Preoperative	6	0.55 (0.47-0.65)	3.2	0.39
		Pre- and postoperative	4	0.56 (0.44-0.71)	0.0	0.78
	Country	China	6	0.53 (0.44-0.63)	0.0	0.59
		Other countries	4	0.60 (0.49-0.73)	0.0	0.64
	Quality of studies	High	5	0.56 (0.47-0.66)	5.8	0.37
		Moderate	5	0.56 (0.45-0.70)	0.0	0.73
Pneumonia		Overall	8	0.38 (0.30-0.48)	0.0	0.89	0.74
	Supplementation type	Multi-strain Probiotics	3	0.61 (0.55-0.67)	5.1	0.34
		Multi-strain Probiotics and synbiotics	5	0.36 (0.26-0.49)	0.0	0.97
	Intervention time	Preoperative	5	0.35 (0.26-0.48)	0.0	0.98
		Pre- and postoperative	3	0.42 (0.29-0.62)	0.0	0.37
	Country	China	5	0.39 (0.29-0.59)	0.0	0.65
		Other countries	3	0.36 (0.25-0.53)	0.0	0.82
	Quality of studies	High	5	0.36 (0.26-0.49)	0.0	0.97
		Moderate	3	0.41 (0.28-0.60)	5.1	0.34
Central line infection		Overall	2	0.34 (0.14-0.81)	11.1	0.28	-
Peritoneal infection		Overall	2	0.42 (0.18-1.01)	0.0	0.89	-
Intra-abdominal infection		Overall	3	0.51 (0.25-1.04)	0.0	0.45	0.50
	Supplementation type	Multi-strain Probiotics and synbiotics	3	0.51 (0.25-1.04)	0.0	0.45
	Intervention time	Preoperative	2	0.78 (0.28-2.02)	0.0	0.55
		Pre- and postoperative	1	0.35 (0.13-0.97)	-	-
	Country	China	2	0.78 (0.28-2.02)	0.0	0.55
		Other countries	1	0.35 (0.13-0.97)	-	-
	Quality of studies	High	3	0.51 (0.25-1.04)	0.0	0.45