Greening et al's study should not have been included. September 2000 Twins have a lower risk of asthma. The quality of systematic reviews. Cochrane Collaboration should ensure equitable participation in management and policy. The quality of systematic reviews.
Criticism is unjustified.
The quality of systematic reviews. High quality reporting of both randomised trials and systematic reviews should be priority. The quality of systematic reviews. Review is biased. Prevalence of atopic asthma in adults has increased.