1. Altman D 1996 Use of confidence intervals to indicate uncertainty in research findings. http://www.acponline.org/journals/ebm/mayjun96/ebconfid.htm. Accessed 10/04/02
2. Clinical utility of hygroscopic heat and moisture exchangers in intensive care patients;Boots;Critical Care Medicine,1997
3. Comparison of three humidification techniques during mechanical ventilation: patient selection, cost and infection considerations;Branson;Respiratory Care,1996
4. Clark MOA (ed) 2000 Cochrane Reviewers Handbook 4.14 (updated October 2001). The Cochrane Library, The Cochrane Collaboration. Update Software, Oxford
5. Mechanical ventilation with heated humidifiers or heat and moisture exchangers: effects on patient colonization and incidence of nosocomial pneumonia;Dreyfuss;American Journal of Respiratory and Critical Care Medicine,1995