On the Patient Global Impression of Change , 2.1 % ( 1/48 ) , 2.1 % ( 1/48 ) , 22.9 % ( 11/48 ) , and 50.0 % ( 24/48 ) of patients in the tapentadol ER group reported that their overall condition was `` very much improved , '' `` much improved , '' `` minimally improved , '' and `` not changed , '' respectively , at Week 1 compared with 0 % , 10.7 % ( 3/28 ) , 28.6 % ( 8/28 ) , and 53.6 % ( 15/28 ) reporting these ratings at Week 8 .