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Table 12.6.a: NNTs equivalant to specific SMDs for various given ‘proportions improved’ in the control group

Control group proportion improved

 

10%

20%

30%

40%

50%

60%

70%

80%

90%

SMD = 0.1

57

33

26

23

23

24

28

37

66

SMD = 0.2 

27 

16 

13 

12 

12 

13 

15 

20 

36 

SMD = 0.5 

 9 

 6 

 5 

 5 

 5 

6 

 7 

 10 

18 

SMD = 0.8 

 5 

 4 

 3 

 3 

 4 

 4 

  5 

 7 

14 

SMD = 1.0 

 4 

 3 

 3 

 3 

 3 

 4 

  5 

 7 

13