Figure 8

Cannulas used for blood collection: three different cannulas were used: a 18G vein catheter (VC), a 21G butterfly vein cannula (BF) and a 22G vacuum cannula (V). The order of the cannulas used was randomized for each subject.

Cannulas used for blood collection: three different cannulas were used: a 18G vein catheter (VC), a 21G butterfly vein cannula (BF) and a 22G vacuum cannula (V). The order of the cannulas used was randomized for each subject.