Table 4 Subgroup analysis for the association of CRT response between groups for each variable
Variable | Subgroups | No. of studies | No. of patients CRT response (Total) | Test of relationship | Heterogeneity (%) | p value for heterogeneity | p value between subgroups | |
|---|---|---|---|---|---|---|---|---|
RR (95%CI) | p value | |||||||
Country | United states or Europe | 6 | 542 (883) | 1.37 (1.23–1.52) | < 0.01 | 0 | 0.76 | 0.24 |
Asia | 1 | 123 (177) | 1.20 (0.98–1.46) | < 0.01 | – | – |  | |
Study design | RCT | 4 | 444 (728) | 1.30 (1.15–1.46) | < 0.01 | 0 | 0.57 | 0.39 |
observational | 3 | 221 (332) | 1.41 (1.21–1.65) | < 0.01 | 0 | 0.66 |  | |
LVEF (%) | ≥ 25 | 4 | 341 (570) | 1.39 (1.21–1.60) | < 0.01 | 12 | 0.33 | 0.37 |
< 25 | 3 | 324 (490) | 1.33 (1.21–1.45) | < 0.01 | 0 | 0.98 |  | |
LVESV (ml) | ≥ 150 | 4 | 447 (667) | 1.25 (1.13–1.40) | < 0.01 | 0 | 0.95 | 0.08 |
< 150 | 3 | 218 (393) | 1.52 (1.26–1.84) | < 0.01 | 0 | 0.78 |  | |
Techniques | ECHO | 3 | 389 (584) | 1.32 (1.17–1.48) | < 0.01 | 0 | 0.5 | 0.73 |
Non-ECHO | 4 | 276 (476) | 1.36 (1.17–1.59) | < 0.01 | 0 | 0.52 |  | |