Table 4 Reliability analysis of OIDP index for Korean participants: OIDP items Correlation matrix

Performances

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

1. eating

1.00

2. speaking

0.39

1.00

3. smiling

0.30

0.48

1.00

4. light physical activities

0.39

0.35

0.22

1.00

5. daily activities

0.38

0.40

0.38

0.73

1.00

6. enjoying contact

0.37

0.53

0.48

0.52

0.74

1.00

7. cleaning teeth

0.37

0.26

0.30

0.13

0.21

0.21

1.00

8. sleeping

0.27

0.25

0.16

0.26

0.32

0.29

0.29

1.00

9. relaxing

0.34

0.21

0.21

0.42

0.37

0.35

0.28

0.41

1.00

10. emotional stability

0.53

0.44

0.43

0.49

0.48

0.54

0.32

0.30

0.42

1.00