At a baseline voided volume of 125 to less than 250 ml the median change in the maximum urinary flow rate was 0.9 and 1.2 ml per second ( p = 0.142 ) in 731 patients , at a baseline of 250 to 450 ml the change was -0.3 and 0.7 ml per second ( p = 0.011 ) in 428 , and at a baseline of greater than 450 ml the change was -0.2 and 2.0 ml per second ( p = 0.186 ) in 38 for placebo and tadalafil , respectively .