Figure 2. Comparison network of the included studies.

The line linked between two drug therapies means there are direct comparisons from original studies. Numbers on the line mean the count number of studies comparing every pair of treatments, which were also reflected by the width of the lines. The size of every node represents the number of randomized participants. ABs  =  α-blockers. 5ARIs  =  5α-reductase inhibitors. MRAs  =  muscarinic receptor antagonists. PDE5-Is  =  phosphodiesterase 5 inhibitors.