Date	Event	Description
30 September 2009	Amended	Change in contact details for Francine Ducharme
16 May 2008	Amended	Converted to new review format.
13 October 2003	New citation required and conclusions have changed	This review represents the second update since its initial publication in The Cochrane Library 2001, Issue 1, May 2001; the first update being in September 2001. The search strategy updated in August 2003 yielded 211 additional citations; 197 citations were excluded for the following mutually exclusive reasons: (1) Duplicate references (N = 91) (2) Not a randomised controlled trial (N = 44), ongoing trial (N=1), or awaiting assessment (N=3) (3) Subjects were not asthmatics (N =4) (4) The tested intervention was not anti‐leukotrienes (N =9) (5) No consistent co‐treatment with inhaled glucocorticoids (N =20) (6) The control intervention was not inhaled corticosteroids (N = 8) (7) Use of non permitted drugs (N=5) (8) The tested intervention was administered for less than 4 weeks (N =5 ) (8) Outcomes not reflective of asthma control (N = 6) (9) Acute care setting (N=1). Fourteen new trials were included in the updated review; ‐7 new trials (2 abstracts contributing little data, 4 full‐text publications and 1 full disclosure of unpublished trial) comparing anti‐leukotrienes versus placebo as add‐on to inhaled glucocorticoids for a total of 13 trials, of which 8 trials contributed data with sufficient details to be aggregated; ‐5 new trials (3 abstracts contributing little data and 2 full‐text publications) comparing anti‐leukotrienes as add‐on to inhaled glucocorticoids versus double‐dose of inhaled steroids for a total of 7 trials, of which 4 trials could be aggregated; ‐2 new trials (both full‐text publications) comparing anti‐leukotrienes versus placebo as add‐on to tapering doses of inhaled glucocorticoids for a total of 7 trials, with 6 trials contributing data that were aggregated. The updated review now comprised 27 trials comparing anti‐leukotrienes versus placebo as add‐on to inhaled glucocorticoids. The systematic review was re‐structured to clearly distinguish trials that use licensed, from those that used higher than licensed, doses of anti‐leukotrienes. The results of the review have not changed markedly as result of the 14 additional trials. The main new feature is the addition of 2 new trials for a total of 3 trials comparing the addition of leukotriene receptor antagonists at LICENSED dose to inhaled glucocorticoids as compared to double‐dose of inhaled glucocorticoids. The two options appear to provide similar benefit although the power is insufficient to assume equivalency.