Table 4.
Summary of subgroup analysis.
| Aerobic exercise group versus usual care. Subgroup: land versus water | |||||||
| Outcome | Indicators | Subgroups | Studies/Participants | Heterogeneity | MD [95% CI]; P | Test for subgroup differences | Total MD [95% CI]; P |
| Lung function | FEV1%pred | Water | 2/80 | Tau2 = 0.00; I2 = 0% | 2.17 [–5.31, 9.66]; .57 | Chi2 = 0.12, df = 1 (P = .73), I2 = 0% | 1.02 [–2.53, 4.57]; .57 |
| Land | 4/145 | Tau2 = 0.00; I2 = 0% | 0.69 [–3.34, 4.72]; .74 | ||||
| FEV1/FVC % | Water | 2/80 | Tau2 = 0.00; I2 = 0% | 0.65 [–4.21, 5.51]; .79 | Chi2 = 0.06, df = 1 (P = .81), I2 = 0% | 0.17 [–2.76, 3.09]; .91 | |
| Dyspnea | Borg | Land | 3/115 | Tau2 = 0.00; I2 = 0% | –0.11 [–3.78, 3.56]; .95 | ||
| Water | 2/69 | Tau2 = 0.22; I2 = 30% | –1.09 [–2.25, 0.07]; .06 | Chi2 = 0.57, df = 1 (P = .45), I2 = 0% | –0.70 [–1.12, –0.27]; .001 | ||
| Land | 5/276 | Tau2 = 0.03; I2 = 10% | –0.61 [–1.08, –0.15]; 0.01 | ||||
| Exercise capacity | 6MWT | Water | 4/118 | Tau2 = 0.00; I2 = 0% | 80.89 [48.67, 113.11]; <.001 | Chi2 = 2.89, df = 1 (P = .09), I2 = 65.4% | 56.37 [32.61, 80.13]; <.001 |
| Land | 7/380 | Tau2 = 586.03; I2 = 45% | 43.94 [16.09, 71.79]; .002 | ||||
| ISWT | Water | 2/57 | Tau2 = 0.00; I2 = 0% | 27.65 [–23.30, 78.59]; .29 | Chi2 = 0.22, df = 1 (P = .64), I2 = 0% | 16.28 [–1.84, 34.41]; .08 | |
| Land | 8/673 | Tau2 = 0.00; I2 = 0% | 14.64 [–4.76, 34.03]; .14 | ||||
| ESWT | Water | 2/60 | Tau2 = 1174.23; I2 = 52% | 339.96 [210.39, 469.53]; <.001 | Chi2 = 1.72, df = 1 (P = .19), I2 = 41.9% | 254.81 [166.41, 343.22]; <.001 | |
| Land | 6/361 | Tau2 = 8405.07; I2 = 54% | 228.18 [122.93, 333.42]; <.001 | ||||
| Muscle strength | ULMS | Water | 1/30 | Not applicable | 0.04 [–0.68, 0.75]; .92 | Chi2 = 0.31, df = 1 (P = .58), I2 = 0% | 0.20 [–0.21, 0.62]; .34 |
| Land | 2/61 | Tau2 = 0.00; I2 = 0% | 0.28 [–0.22, 0.79]; .27 | ||||
| LLMS | Water | 1/30 | Not applicable | 0.22 [–0.50, 0.94]; .56 | Chi2 = 0.44, df = 1 (P = .51), I2 = 0% | 0.00 [–0.34, 0.35]; .98 | |
| Land | 2/99 | Tau2 = 0.00; I2 = 0% | –0.06 [–0.46, 0.33]; .76 | ||||
Note: ULMS and LLMS due to the results of different measurements using standardized mean differences (SMD).
6MWT = 6-minute walking test, CI = confidence interval, ESWT = endurance shuttle walk test, FEV1/FVC = ratio of forced expiratory volume in the first second to forced vital capacity, ISWT = incremental shuttle walk test, LLMS = lower limb muscle strength, MD = mean difference, ULMS = upper limb muscle strength.