Table 2—

Combined analysis for arterial oxygen tension in chronic obstructive pulmonary disease randomised controlled trials(RCTs)

First author [Ref.]Bilevel NIPPVControlWeight %WMD (random) 95% CI
nMean±sdnMean±sd
Casanova 112056.30±8.202457.30±6.5024.80−1.00 (−5.44–3.44)
Clini 232369.00±8.252465.00±6.0027.694.00 (−0.14–8.14)
Diaz 191853.77±7.951850.47±6.0023.373.30 (−1.30–7.90)
Garrod 241766.10±8.552066.80±9.3815.86−0.70 (−6.48–5.08)
Gay 21470.50±4.70660.30±14.403.8110.20 (−2.21–22.61)
Renston 22966.00±15.00867.00±8.484.47−1.00 (−12.43–10.43)
Total911001001.86 (−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).