First author [Ref.] | Bilevel NIPPV | Control | Weight % | WMD (random) 95% CI | ||
n | Mean±sd | n | Mean±sd | |||
Casanova 11 | 20 | 56.30±8.20 | 24 | 57.30±6.50 | 24.80 | −1.00 (−5.44–3.44) |
Clini 23 | 23 | 69.00±8.25 | 24 | 65.00±6.00 | 27.69 | 4.00 (−0.14–8.14) |
Diaz 19 | 18 | 53.77±7.95 | 18 | 50.47±6.00 | 23.37 | 3.30 (−1.30–7.90) |
Garrod 24 | 17 | 66.10±8.55 | 20 | 66.80±9.38 | 15.86 | −0.70 (−6.48–5.08) |
Gay 21 | 4 | 70.50±4.70 | 6 | 60.30±14.40 | 3.81 | 10.20 (−2.21–22.61) |
Renston 22 | 9 | 66.00±15.00 | 8 | 67.00±8.48 | 4.47 | −1.00 (−12.43–10.43) |
Total | 91 | 100 | 100 | 1.86 (−0.60–4.32) |
NIPPV: noninvasive positive pressure ventilation; WMD: weighted mean difference; CI: confidence interval. Comparison: RCT trials of bilevel NIPPV versus all modalities (long-term oxygen therapy, sham ventilation, exercise). Outcome: arterial oxygen tension cmH2O. Test for heterogeneity: Chi squared = 5.73, df = 5 (p = 0.33), I2 = 12.7%. Test for overall effect: Z = 1.49 (p = 0.14).