Data collection and analysis:
Data from all trials were combined using the Review Manager (version 4.1). We planned to perform: 1) random effects weighted mean difference (WMD), with 95% confidence intervals (95% CI), 2) Homogeneity of effect sizes with the Dersimonian and Laird method with p<0.1 as the cut point for significance, and 3) sensitivity analysis on different helium-oxygen mixtures (80/20 vs 70/30), and 4) methodological quality (Jadad score >2 vs. <3). An update search conducted in September 2002 identified one further excluded study.
This record should be cited as:
Rodrigo GJ., Pollack CV, Rodrigo C, Rowe BH, Walters EH. Heliox for treatment of exacerbations of chronic obstructive pulmonary disease. Cochrane Database of Systematic Reviews 2002, Issue 2. Art. No.: CD003571. DOI: 10.1002/14651858.CD003571