When patients were stratified into different baseline Sexual Health Inventory for Men subgroups , the pre-intervention and post-intervention difference in low-intensity extracorporeal shockwave therapy was found to be significant in the subgroup with severe erectile dysfunction ( low-intensity extracorporeal shockwave therapy International Index of Erectile Function-ED domain improvement : 10.14.1 vs sham therapy International Index of Erectile Function-ED domain improvement : 3.23.3 ; P = 0.003 ) .