Table 2 Structural validity: Factor loadings of the WHOQOL-BREF items in Principal Component Analysis with Varimax rotation

Physical QOL

4.73

19.69%

3

Constrains by physical pain

Phy

0.684

0.816

0.002

0.073

0.113

4

Dependency on medical treatment

Phy

0.382

0.582

0.207

0.001

0.024

10

Energy

Phy

0.630

0.701

0.356

0.102

0.031

14

Opportunity for leisure activities

Env

0.562

0.648

0.205

0.283

0.139

15

Mobility

Phy

0.655

0.786

− 0.044

0.173

0.075

16

Satisfaction with sleep

Phy

0.459

0.599

0.256

− 0.038

0.184

17

Activities of daily living

Phy

0.738

0.809

0.255

0.100

0.091

18

Work capacity

Phy

0.643

0.741

0.286

0.088

0.068

Psychological QOL

4.17

17.38%

5

Enjoy life

Psy

0.693

0.201

0.757

0.280

− 0.011

6

Meaningful life

Psy

0.687

0.120

0.765

0.296

− 0.007

7

Concentration

Psy

0.547

0.396

0.590

− 0.088

0.185

8

Safety in daily life

Env

0.548

0.192

0.616

0.029

0.361

9

Healthy physical environment

Env

0.237

0.082

0.418

0.171

0.162

11

Acceptance of bodily appearance

Psy

0.267

0.087

0.403

0.101

0.294

19

Satisfaction with oneself

Psy

0.619

0.335

0.643

0.243

0.184

26

Absence of negative feelings

Psy

0.586

0.265

0.690

0.092

0.175

Social QOL

2.03

8.47%

20

Personal relationships

Soc

0.606

0.201

0.534

0.524

0.078

21

Satisfaction with sex life

Soc

0.466

0.272

0.240

0.553

− 0.171

22

Satisfaction with support from friends

Soc

0.443

0.070

0.277

0.572

0.183

23

Satisfaction with home environment

Env

0.435

− 0.011

0.149

0.577

0.282

Environmental QOL

2.20

9.16%

12

Financial resources

Env

0.608

0.067

0.357

− 0.062

0.687

13

Availability of information

Env

0.486

0.137

0.216

0.051

0.646

24

Access to health services

Env

0.594

0.135

0.103

0.380

0.649

25

Satisfaction with access to transport

Env

0.556

0.151

− 0.067

0.465

0.559