Table 5 Factor analysis of EQ-5D+ and OHIP-14 items

Factor

Eigen-value

Variance (%)

Item

Item label

1

2

3

4

h²

1

8.44

42.2

EQ1

Mobility problems

.068

.097

.844

-.031

.73

2

1.71

8.6

EQ2

Self-care problems

.045

-.088

.776

.142

.63

3

1.37

6.9

EQ3

Problems with usual activities

.066

.368

.500

.121

.40

4

1.05

5.3

EQ4

Pain/discomfort

-.001

.829

.070

.154

.72

5

0.91

4.6

EQ5

Anxiety/depression

.158

.351

.071

.693

.63

6

0.81

4.1

EQ6

Cognition

.187

.032

.122

.820

.72

7

0.77

3.9

OH1

Trouble pronouncing words

.672

.087

.354

.062

.59

8

0.66

3.3

OH2

Sense of taste worsened

.575

.278

.152

.177

.46

9

0.61

3.1

OH3

Painful aching in mouth

.286

.709

.035

.013

.59

10

0.56

2.8

OH4

Uncomfortable eating

.503

.596

.092

-.029

.62

11

0.50

2.5

OH5

Felt self-conscious

.838

.161

-.074

.065

.74

12

0.39

2.0

OH6

Felt tense

.681

.479

-.014

.176

.72

13

0.37

1.9

OH7

Diet unsatisfactory

.578

.448

.252

.154

.62

14

0.35

1.8

OH8

Interrupt meals

.540

.519

.180

.029

.59

15

0.34

1.7

OH9

Difficulty relaxing

.600

.577

.075

.179

.73

16

0.30

1.5

OH10

Been embarrassed

.881

.040

-.039

.145

.80

17

0.29

1.4

OH11

Irritable with other people

.471

.593

-.031

.149

.60

18

0.26

1.3

OH12

Difficulty doing usual jobs

.561

.531

.078

.157

.63

19

0.17

0.9

OH13

Life less satisfying

.618

.464

.039

.305

.69

20

0.12

0.6

OH14

Unable to function

.189

.500

.087

.260

.36

Variance (%):

25.3

20.3

9.4

7.8