From: A new instrument for measuring anticoagulation-related quality of life: development and preliminary validation
Difference score (t2-t1)
Frequency
<= -21
2
-16 to -20
3
-15 to -11
9
-10 to -6
16
-5 to -1
0
1
1 to 5
20
6 to 10
15
11 to 15
14
16 to 20
> = 21
6