Table 3 Factor analysis of the Japanese version of the Barriers Questionnaire-II completed by patients (main factor method: promax rotated factor pattern) and confidence coefficients

Factor I: Physiological Effects

α = 0.89

7. Physiological Effects: Monitor 1

.834

−.017

−.074

−.114

.039

15. Physiological Effects: Tolerance 2

.784

−.060

−.234

.160

.248

2. Harmful Effects: Addiction 1

.649

−.046

.091

−.064

−.278

16. Physiological Effects: Monitor 2

.624

.054

.062

.040

.080

9. Harmful Effects: Addiction 2

.604

−.015

.080

.007

−.064

6. Physiological Effects: Tolerance 1

.592

−.146

.203

.025

.187

21. Physiological Effects: Tolerance 3

.523

.261

−.011

.116

.117

23. Harmful Effects: Addiction 3

.511

.127

.104

.259

−.016

3. Physiological Effects: SE1 (Drowsiness)

.482

−.089

.069

−.166

−.145

10. Physiological Effects: SE3 (Nausea)

.430

.014

.121

−.165

−.015

22. Physiological Effects: Monitor 3

.401

.247

.163

.177

.047

Factor II: Communication

α = 0.78

26. Communication: Distract MD 3

−.198

.943

.001

−.020

.018

12. Communication: Distract MD 1

.257

.680

−.193

−.125

−.071

11. Communication: Be good 1

.012

.654

−.021

−.155

−.084

20. Physiological Effects: SE6 (general item)

.159

.561

−.029

−.087

−.288

27. Communication: Be good 3

−.354

.524

.138

.111

.164

25. Communication: Be good 2

−.118

.508

.150

.066

.311

18. Communication: Distract MD 2

.238

.461

.023

−.038

−.118

Factor III: Harmful Effects

α = 0.86

4. Harmful Effects: Immune system 1

.018

−.106

1.034

−.103

−.065

13. Harmful Effects: Immune system 2

.109

−.069

.822

−.004

−.028

19. Harmful Effects: Immune system 3

.210

−.018

.614

.038

.049

17. Physiological Effects: SE5 (Constipation)

.001

.146

.492

.010

.079

5. Physiological Effects: SE2 (Confusion)

.221

.180

.407

.050

.015

14. Physiological Effects: SE4 (Embarrassment)

.116

.151

.296

.042

−.080

Factor IV: Disease Progression

α = 0.92

29. Disease Progression 2

−.101

.043

−.032

.963

−.089

30. Disease Progression 3

−.012

−.041

−.032

.939

−.094

28. Disease Progression 1

.021

−.262

.013

.863

−.094

Factor V: Fatalism

α = 0.73

1. Fatalism 1

.121

−.014

−.017

−.121

.716

8. Fatalism 2

−.049

−.060

−.075

−.016

.704

24. Fatalism 3

.041

−.125

.049

−.201

.657

I

II

III

IV

V

–

.365

.600

.394

.083

–

.539

.238

.365

–

.197

.203

–

.101

–