Welsh, Emma J
Normansell, Rebecca A
Cates, Christopher J
Article History
First Online: 19 March 2015
Competing interests
: We are employees of the Cochrane Airways Group with editorial responsibility for the reviews that are published. EW and CC have authored Cochrane reviews included in this analysis. The Cochrane Airways Group is a part of the international Cochrane Collaboration, an independent not-for-profit consortium dedicated to providing up-to-date accurate information about the effects of health care. The National Institute for Health Research (NIHR) is the largest single funder of the Cochrane Airways Group.