Abstract
I present methods for assessing the relative effectiveness of two treatments when they have not been compared directly in a randomized trial but have each been compared to other treatments. These network meta‐analysis techniques allow estimation of both heterogeneity in the effect of any given treatment and inconsistency (‘incoherence’) in the evidence from different pairs of treatments. A simple estimation procedure using linear mixed models is given and used in a meta‐analysis of treatments for acute myocardial infarction. Copyright © 2002 John Wiley & Sons, Ltd.