Incidence [ odds ratio ( OR ) 0.39 , 95 % confidence interval ( CI ) ( 0.16-0 .96 ) , P = 0.04 ] and incidence rates [ incidence rate ratio ( IRR ) 0.41 , 95 % CI 0.17-0 .97 , P = 0.05 ] of MRSA AI were significantly lower with the use of M/C .