At posttraining the CSC group ( n = @ ) scored significantly higher on a procedure-specific skill scale compared with the CT group ( n = @ ) -LSB- median , @ ( interquartile range , @-@ @ ) vs @ ( @-@ @ ) , P = @ -RSB- , and made fewer technical errors -LSB- @ ( @-@ ) vs @ ( @-@ ) , P = @ -RSB- .