Patients were accurately stratified with an actual risk of 1.0 % , 3.2 % and 9.7 % in the bottom , middle and top tertile of the score , respectively , with corresponding hazard ratios of 3.5 ( 95 % CI 2.0-6 .2 ) and 10.5 ( 95 % CI 6.3-17 .6 ) for the middle and top tertile compared to the bottom tertile ( both p < 0.0001 ) .
