Abstract
Studies comparing more than two competing therapies are common in several fields, but standard meta-analytic methods can make only pairwise comparisons. The meth ods proposed in this article, a generalization of current meta-analytic methods, allow for any number of competing therapies and include both fixed- and random-effects models. Key words: meta-analysis; random-effects models; multiple treatment studies. (Med Decis Making 1998;18:37-43)