Table 2.

Results Meta-Analysis and Meta-Regression

	No. of Studies	No. of Participants	Relative Risk (95% CI; I2)†	Explained Heterogeneity (p-Value)
Hospitalization	22	6,586	0.82 (0.72–0.94; 84%)*
Quality
Poor	1	276	1.12 (0.84–1.50; NA)	1.7% (.616)
Moderate	8	1,868	0.78 (0.53–1.14; 92%)
Good	13	4,442	0.86 (0.78–0.96; 61%)*
Length of follow-up
<1 year	10	2,590	0.81 (0.58–1.12; 91%)	3.1% (.566)
≥1 year	12	3,996	0.85 (0.77–0.95; 60%)*
Number of components
2	3	361	1.02 (0.82–1.25; 0%)	1% (.789)
3	8	2,186	0.69 (0.49–0.97; 94%)*
4	11	4,039	0.91 (0.83–1.01; 54%)
Mortality	27	6,832	0.82 (0.76–0.93; 0%)*
Quality
Poor	3	474	0.69 (0.50–0.95; 10%)*	No heterogeneity (.915)
Moderate	8	1,797	1.00 (0.78–1.28; 21%)
Good	15	4,327	0.79 (0.67–0.93; 30%)*
Length of follow-up
<1 year	11	2,268	0.94 (0.74–1.18; 0%)	No heterogeneity (.781)
≥1 year	16	4,564	0.79 (0.68–0.91; 29%)*
Number of components
2	5	692	0.67 (0.50–0.91; 8%)*	No heterogeneity (.191)
3	10	2,050	0.88 (0.69–1.13; 19%)
4	12	4,090	0.85 (0.73–0.98; 17%)*
			Mean Difference (95% CI;I2)‡
Quality of life	7	992	−7.14 (−9.55–4.72; 78%)*
Quality
Poor	0	NA	NA	NA
Moderate	4	588	−6.65 (−14.19–0.88; 78%)
Good	3	404	−10.93 (−16.96 to −5.71; 50%)*
Length of follow-up
<1 year	5	692	−10.64 (−15.77 to −5.51; 78%)*	NA
≥1 year	2	300	−1.71 (−10.68–7.25; 63%)
Number of components
2	1	72	−21.00 (−33.23 to −8.77; NA)*	NA
3	3	456	−9.19 (−14.67 to −3.70; 56%)*
4	3	464	−4.32 (−14.46 to 5.82; 85%

Boldface type indicates overall analysis.

^*p-value < .05.

^†Relative risk for CCM within the various subgroups.

^‡Mean difference for CCM within the various subgroups; CI, confidence interval; I², statistical heterogeneity.