Statistically significant differences were found in the incidence rate of urinary tract infection between the control and trial groups ( 20.3 % [ 24/118 ] vs 7.3 % [ 10/138 ] , P < 0.01 ) , as well as in those with diabetes mellitus ( 6.7 % [ 3/45 ] vs 23.5 % [ 8/34 ] , P < 0.05 ) , those with residual urine > 50 ml ( 5.4 % [ 3/56 ] vs 18.5 % [ 10/54 ] , P < 0.05 ) , and those with both diabetes mellitus and residual urine ( 9.5 % [ 2/21 ] vs 44.4 % [ 8/18 ] , P < 0.05 ) .