Level

Cases (n = 236)

%

0

18

7.6

1

28

11.9

2

16

6.8

3a

44

18.6

3b

94

39.8

4a

1

0.4

4b

6

2.5

5

15

6.4

Others

14

5.9

‚Č•Level 3b

116

49.2