Doktor went on to win 14 medals at the ICF Canoe Sprint World Championships, including two golds (C-1 200 m: 1998, C-1 500 m: 1997), nine silvers (C-1 200 m: 1997, 1999, 2003; C-1 500 m: 1995, 1999; C-1 1000 m: 1995, 1997, 1998, 2001), and three bronzes (C-1 500 m: 2003, C-1 1000 m: 1999, C-4 1000 m: 1998). He was also European C-1 1000 m champion in 1997 and 2000.