Table 6.
Summary of evidence.
| Citation | Outcomes | Studies (participants) | Heterogeneity | Relative effect (95% CI) | P value |
|---|---|---|---|---|---|
| Cao et al. [21] | FEV1 | 17 (1,395) | 83% | MD = 0.23 (0.15, 0.31) | P < 0.00001 |
| FVC | 13 (1,033) | 61% | MD = 0.19 (0.08, 0.30) | P = 0.0007 | |
| FEV1/FVC | 20 (1,808) | 74% | MD = 3.85 (2.19, 5.51) | P < 0.00001 | |
| 6-MWD | 18 (1,562) | 96% | MD = 43.83 (29.47, 58.20) | P < 0.00001 | |
| SGRQ | 4 (280) | 54% | MD = −7.71 (−10.54, −4.89) | P < 0.00001 | |
| CAT | 7 (802) | 78% | MD = −2.56 (−4.13, −1.00) | P = 0.001 | |
|
| |||||
| Liu et al. [22] | 6-MWD | 10 (1,160) | 66% | Hedge′s g = 0.69 (0.44, 0.94) | P < 0.001 |
| FEV1 | 10 (809) | 68% | Hedge′s g = 0.47 (0.22, 0.73) | P < 0.001 | |
| FEV1% | 13 (1,417) | 54% | Hedge′s g = 0.38 (0.21, 0.56) | P < 0.001 | |
| FVC | 8 (674) | 14% | Hedge′s g = 0.39 (0.22, 0.56) | P < 0.001 | |
| FEV1/FVC | 13 (1,284) | 53% | Hedge′s g = 0.5 (0.33, 0.68) | P < 0.001 | |
| Quality of life | 7 (746) | 77% | Hedge′s g = −0.45 (-0.77, -0.12) | P < 0.05 | |
|
| |||||
| Chen et al. [23] | FEV1 | 7 (525) | 0% | MD = 0.25 (0.12, 0.38) | P < 0.001 |
| FEV1% | 10 (1,005) | 26% | MD = 6.71 (4.25, 9.18) | P < 0.001 | |
| FVC | 6 (423) | 42% | MD = 0.16 (0.01, 0.31) | P = 0.04 | |
| FEV1/FVC | 9 (925) | 71% | MD = 4.90 (2.43, 7.38) | P < 0.001 | |
| CAT | 5 (679) | 78% | MD = −1.84 (-3.50, -0.19) | P < 0.05 | |
|
| |||||
| Han et al. [24] | 6-MWD | 4 (346) | 28% | MD = 45.27 (40.11, 50.42) | P < 0.01 |
| FEV1 | 5 (450) | 82% | MD = 0.26 (0.14, 0.37) | P < 0.01 | |
| FEV1% | 7 (775) | 36% | MD = 6.02 (5.02, 7.01) | P < 0.01 | |
| FVC | 3 (266) | 0% | MD = 0.27 (0.06, 0.48) | P = 0.01 | |
| FEV1/FVC | 6 (423) | 85% | MD = 3.63 (-0.18, 7.43) | P = 0.06 | |
|
| |||||
| Li et al. [25] | FEV1/pred% | 9 (985) | 67% | MD = 6.86 (4.13, 9.60) | P < 0.01 |
| FEV1 | 4 (346) | 75% | MD = 0.30 (0.14, 0.46) | P < 0.01 | |
| FEV1% | 8 (905) | 73% | MD = 4.50 (1.84, 7.16) | P < 0.01 | |
| FVC | 3 (246) | 0% | MD = 0.34 (0.13, 0.54) | P < 0.01 | |
| 6-MWD | 6 (476) | 92% | MD = 56.35 (37.55, 75.16) | P < 0.01 | |
|
| |||||
| Xie et al. [26] | 6-MWD | 12 (895) | 83% | SMD = 1.33 (0.97, 1.68) | P < 0.001 |
| FEV1 | 12 (895) | 94% | SMD = 1.05 (0.56, 1.55) | P < 0.001 | |
| FEV1% | 15 (1,848) | 86% | SMD = 0.50 (0.24, 0.76) | P = 0.0002 | |
| FVC | 9 (925) | 68% | SMD = 0.26 (0.03, 0.50) | P = 0.03 | |
| FEV1/FVC | 14 (1,762) | 83% | SMD = 0.44 (0.20, 0.68) | P = 0.0004 | |
| CAT | 3 (443) | 87% | SMD = −0.56 (-1.24, 0.12) | P = 0.11 | |
| SGRQ | 3 (762) | 81% | SMD = −1.36 (-1.74,-0.98) | P < 0.001 | |
| WHOQOL-BREF | 2 (852) | 73% | SMD = 0.94 (0.66, 1.22) | P < 0.001 | |
|
| |||||
| Xiao et al. [27] | MRC | 3 (136) | 62% | MD = −0.73 (-1.13, -0.33) | P < 0.05 |
| 6-MWD | 6 (274) | 0% | MD = 17.78 (7.97, 27.58) | P < 0.05 | |
| FEV1 | 8 (502) | 83% | MD = 0.23 (0.07, 0.38) | P < 0.05 | |
| FEV1/pred% | 10 (580) | 97% | MD = 7.59 (2.92, 12.26) | P < 0.05 | |
| FEV1/FVC | 12 (769) | 95% | MD = 6.81 (3.22, 10.40) | P < 0.05 | |
| CAT | 4 (341) | 56% | MD = −2.29 (-3.27, -1.30) | P < 0.05 | |
| SGRQ | 5 (297) | 63% | MD = −9.85 (-13.13, -6.56) | P < 0.05 | |
|
| |||||
| Gao et al. [28] | MRC | 3 (459) | 42% | MD = −0.73 (-0.96, -0.50) | P < 0.001 |
| 6-MWD | 9 (805) | 43% | MD = 21.89 (14.67, 29.11) | P < 0.001 | |
| FEV1 | 9 (560) | 5% | MD = 0.19 (0.13, 0.24) | P < 0.001 | |
| FEV1% | 13 (861) | 57% | MD = 7.14 (6.09, 8.18) | P < 0.001 | |
| FEV1/FVC | 13 (890) | 83% | MD = 4.2 (3.26, 5.14) | P < 0.001 | |
| Quality of life | 7 (780) | 56% | SMD = −0.84 (-1.12, -0.55) | P < 0.001 | |
|
| |||||
| Liu et al. [29] | 6-MWD | 5 (326) | 0% | MD = 22.62 (10.49, 34.75) | P < 0.05 |
| FEV1 | 5 (247) | 0% | MD = 0.10 (0.01, 0.18) | P < 0.05 | |
| FEV1% | 5 (247) | 24% | MD = 3.08 (0.18, 5.97) | P = 0.04 | |
|
| |||||
| Zhang et al. [30] | MRC | 5 (228) | 22% | MD = −0.55 (-0.75, -0.36) | P < 0.001 |
| 6-MWD | 9 (475) | 74% | MD = 33.76 (18.99, 48.52) | P < 0.001 | |
| FEV1 | 6 (337) | 67% | MD = 0.19 (0.06, 0.31) | P = 0.01 | |
| FEV1% | 13 (644) | 89% | MD = 6.08 (2.55, 9.62) | P = 0.0007 | |
| CAT | 4 (266) | 4% | MD = −2.69 (-3.34, -2.03) | P < 0.001 | |
|
| |||||
| Tong et al. [31] | 6-MWD | 8 (629) | 90% | MD = 30.57 (19.61, 41.53) | P < 0.001 |
| FEV1 | 5 (449) | 90% | MD = 0.32 (0.09, 0.56) | P < 0.001 | |
| FEV1/FVC | 6 (535) | 47% | MD = 2.66 (1.32, 2.26) | P < 0.001 | |
| FEV1% | 5 (455) | 61% | MD = 6.04 (2.58, 9.5) | P = 0.006 | |
| CAT | 3 (258) | 84% | MD = −5.54 (-9.49, -1.59) | P = 0.002 | |
|
| |||||
| Li et al. [32] | FEV1% (3 months) | 10 (695) | 36% | MD = 5.34 (2.70, 7.98) | P < 0.001 |
| FEV1% (6 months) | 9 (1,006) | 86% | MD = 5.35 (2.58, 8.12) | P = 0.0001 | |
| FEV1/FVC (3 months) | 10 (695) | 66% | MD = 4.49 (1.66, 7.31) | P = 0.002 | |
| FEV1/FVC (6 months) | 11 (926) | 79% | MD = 2.53 (0.38, 4.68) | P = 0.02 | |
| CAT | 5 (262) | 6% | MD = −4.18 (-5.52, -2.84) | P < 0.001 | |
| 6-MWD (3 months) | 6 (480) | 45% | MD = 22.10 (12.43, 31.78) | P < 0.001 | |
| 6-MWD (6 months) | 9 (628) | 95% | MD = 44.46 (20.59, 68.34) | P < 0.001 | |
|
| |||||
| Yuan et al. [33] | FEV1 | 4 (258) | 73% | MD = 0.39 (0.21, 0.57) | P < 0.001 |
| FEV1% | 4 (273) | 97% | MD = 4.41 (-1.97, 10.79) | P = 0.18 | |
| FEV1/FVC | 8 (577) | 97% | MD = 10.39 (5.44, 15.35) | P < 0.001 | |
| FEV1/pred% | 4 (324) | 95% | MD = 8.44 (0.40, 16.48) | P = 0.04 | |
| 6-MWD | 4 (278) | 93% | MD = 63.42 (34.06, 92.79) | P < 0.001 | |
Note: SMD: standardized mean difference; MD: mean difference; FEV1: forced expiratory volume in one second; FVC: forced vital capacity; 6-MWD: 6 min walking distance; FEV1/FVC: the amount of air exhaled in the first second divided by all of the air exhaled during a maximal exhalation; SGRQ: St George's respiratory questionnaire; CAT: COPD assessment test; FEV1%: percentage of the forced expiratory volume in one second; QOL: quality of life; WHOQOL-BREF: the World Health Organization on quality of life brief scale; MRC: medical research council dyspnea scale; FEV1%pred: the percentage of predicted values of FEV1.