Introduction
Methods
Sample
Measures
Statistical analysis
Sample comparisons
Variable | Asian (n = 171 | Non-Asian (n = 270) | Difference, Asian vs. Non-Asian | ||||||
---|---|---|---|---|---|---|---|---|---|
Mean | SD | Mean | SD | t | Chi-square | p-value | Variance explained | ||
Age | 47.13 | 15.25 | 46.13 | 14.97 | 0.68 | 0.50 | 0.001 | ||
Years Since Diagnosis | 8.72 | 8.28 | 9.39 | 9.05 | -0.77 | 0.44 | 0.001 | ||
Baseline BMI | 23.72 | 3.86 | 25.93 | 4.64 | -5.14 | < .0005 | 0.059 | ||
No. | % | No. | % | ||||||
Female | 71 | 42% | 138 | 51% | 3.86 | 0.05 | 0.009 | ||
Region | Europe | 5 | 3% | 214 | 79% | 346.74 | < .0005 | 0.787 | |
Japan | 47 | 27% | 0 | 0% | |||||
Latin America | 1 | 1% | 21 | 8% | |||||
North America | 9 | 5% | 24 | 9% | |||||
Rest of Asia Pacific | 109 | 64% | 11 | 4% | |||||
Other variables included in propensity score | |||||||||
Trial | 43.75 | < .0005 | 0.099 | ||||||
301 | 129 | 75% | 117 | 43% | |||||
302 | 42 | 25% | 153 | 57% | |||||
Observed LDH category | 44.23 | < .0005 | 0.100 | ||||||
LDH < 1.5xULN | 42 | 25% | 153 | 57% | |||||
LDH 1.5—< 3xULN | 16 | 9% | 18 | 7% | |||||
LDH > = 3xULN | 113 | 66% | 99 | 37% | |||||
Observed pRBC stratum | 49.22 | < .0005 | 0.112 | ||||||
Not measured | 42 | 25% | 153 | 57% | |||||
0 unit pRBC | 24 | 14% | 19 | 7% | |||||
1–14 units pRBC | 74 | 43% | 82 | 30% | |||||
> 14 units pRBC | 31 | 18% | 16 | 6% | |||||
Immuno-suppressant treatment | 57 | 33% | 167 | 62% | 34.07 | .0005 | 0.077 | ||
Aplastic anemia | 60 | 35% | 92 | 34% | 0.05 | 0.83 | < .001 | ||
Myelodysplastic syndrome | 8 | 5% | 14 | 5% | 0.06 | 0.81 | < .001 | ||
Bone marrow disorder | 66 | 39% | 100 | 37% | 0.11 | 0.74 | < .001 |
Missing-data imputation for propensity scores.
Multivariate models
DIF comparisons
where P(Y ≤ j) represents the probability that j is the rating-scale response category,Model 1: Logit[P(Y≤j)] = αj + b1(Total Score);Model 2: Logit[P(Y≤j)] = αj + b1(Total Score) + b2(Group); andModel 3: Logit[P(Y≤j)] = αj + b1(Total Score) + b2(Group) + b3(Total Score * Group),
Results
Sample
Propensity scores
Baseline multivariate models
Subscale | B for Asian group | SE | p** | Cohen's d |
---|---|---|---|---|
Function scales (higher is better) | ||||
GlobalHealthStatus/QOL | −1.11 | 2.31 | 0.63 | −0.05 |
Physical functioning | 3.09 | 2.03 | 0.13 | 0.16 |
Role functioning | 5.86 | 2.91 | 0.04 | 0.22 |
Emotional functioning | 5.66 | 2.49 | 0.02 | 0.25 |
Cognitive functioning | −3.05 | 2.45 | 0.22 | −0.14 |
Social functioning | −1.57 | 2.86 | 0.58 | −0.06 |
Symptom scales (higher is worse) | ||||
Fatigue | −0.48 | 2.70 | 0.86 | −0.02 |
Nausea and vomiting | 0.81 | 1.50 | 0.59 | 0.06 |
Pain | 0.74 | 2.66 | 0.78 | 0.03 |
Dyspnoea | −1.91 | 3.10 | 0.54 | −0.07 |
Insomnia | −1.81 | 3.10 | 0.56 | −0.06 |
Appetite loss | 1.21 | 2.37 | 0.61 | 0.06 |
Constipation | 5.21 | 2.24 | 0.02 | 0.25 |
Diarrhea | 6.56 | 2.01 | 0.00 | 0.36 |
Financial difficulties | 4.98 | 3.29 | 0.13 | 0.17 |
Longitudinal multivariate models
Subscale | b | SE | p** | Pseudo-R2 increment |
---|---|---|---|---|
Function scales (higher is better) | ||||
GlobalHealthStatus/QOL | −1.29 | 1.71 | 0.45 | −0.0001 |
Physical functioning | 1.07 | 1.51 | 0.48 | 0.0000 |
Role functioning | 2.80 | 1.90 | 0.14 | −0.0001 |
Emotional functioning | 2.55 | 1.78 | 0.15 | 0.0000 |
Cognitive functioning | −2.25 | 1.81 | 0.21 | 0.0001 |
Social functioning | −1.80 | 1.95 | 0.36 | 0.0001 |
Symptom scales (higher is worse) | ||||
Fatigue | 0.45 | 1.94 | 0.82 | 0.0000 |
Nausea and vomiting | 0.61 | 0.61 | 0.32 | −0.0001 |
Pain | 0.63 | 1.49 | 0.67 | 0.0000 |
Dyspnoea | −2.87 | 2.02 | 0.15 | −0.0002 |
Insomnia | −1.67 | 2.13 | 0.43 | −0.0002 |
Appetite loss | 2.98 | 1.27 | 0.02 | −0.0005 |
Constipation | 3.06 | 1.61 | 0.06 | 0.0004 |
Diarrhea | 3.00 | 1.25 | 0.02 | 0.0003 |
Financial difficulties | 4.93 | 2.32 | 0.03 | 0.0002 |
Baseline DIF comparisons
Item no | Item content | Domain | Test of uniform DIF | Test of non-uniform DIF | Test of Uniform and non-uniform DIF | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
LR Chi2 | P-value | Change in R2 | DIF size | "Favored" group | Odds Ratio | LR Chi2 | P-value | Change in R2 | DIF size | LR Chi2 | P-value | Change in R2 | DIF size | |||
eortc29 | 29. How would you rate your overall health during the past week? | Global | 5.56 | 0.018 | 0.004 | Negligible | Non-Asian | 0.51 | NS | NS | NS | NS | NS | NS | NS | NS |
eortc30 | 30. How would you rate your overall quality of life during the past week? | Global | 4.94 | 0.026 | 0.003 | Negligible | Asian | 1.90 | NS | NS | NS | NS | NS | NS | NS | NS |
eortc01 | 1. Do you have any trouble doing strenuous activities, like carrying a heavy shopping bag or a suitcase? | Physical | 6.04 | 0.014 | 0.006 | Negligible | Non-Asian | 0.56 | NS | NS | NS | NS | 7.47 | 0.024 | 0.007 | Negligible |
eortc02 | 2. Do you have any trouble taking a long walk? | Physical | 6.99 | 0.008 | 0.006 | Negligible | Asian | 1.91 | NS | NS | NS | NS | 9.01 | 0.011 | 0.008 | Negligible |
eortc03 | 3. Do you have any trouble taking a short walk outside of the house? | Physical | NS | NS | NS | NS | NS | NS | 6.29 | 0.012 | 0.010 | Negligible | 6.75 | 0.034 | 0.011 | Negligible |
eortc04 | 4. Do you need to stay in bed or a chair during the day? | Physical | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc05 | 5. Do you need help with eating, dressing, washing yourself or using the toilet? | Physical | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc06 | 6. Were you limited in doing either your work or other daily activities? | Role | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc07 | 7. Were you limited in pursuing your hobbies or other leisure time activities? | Role | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc21 | 21. Did you feel tense? | Emotional | 7.10 | 0.008 | 0.008 | Negligible | Non-Asian | 0.49 | NS | NS | NS | NS | 10.28 | 0.006 | 0.012 | Negligible |
eortc22 | 22. Did you worry? | Emotional | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc23 | 23. Did you feel irritable? | Emotional | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc24 | 24. Did you feel depressed? | Emotional | 9.83 | 0.002 | 0.011 | Negligible | Asian | 2.26 | NS | NS | NS | NS | 13.57 | 0.001 | 0.015 | Negligible |
eortc20 | 20. Have you had difficulty in concentrating on things, like reading a newspaper or watching television? | Cognitive | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc25 | 25. Have you had difficulty remembering things? | Cognitive | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc26 | 26. Has your physical condition or medical treatment interfered with your family life? | Social | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc27 | 27. Has your physical condition or medical treatment interfered with your social activities? | Social | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc10 | 10. Did you need to rest? | Fatigue | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc12 | 12. Have you felt weak? | Fatigue | 14.76 | 0.000 | 0.014 | Negligible | Asian | 2.84 | NS | NS | NS | NS | 14.84 | 0.001 | 0.014 | Negligible |
eortc18 | 18. Were you tired? | Fatigue | 4.77 | 0.029 | 0.005 | Negligible | Non-Asian | 0.54 | NS | NS | NS | NS | NS | NS | NS | NS |
eortc14 | 14. Have you felt nauseated? | Nausea | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc15 | 15. Have you vomited? | Nausea | 4.41 | 0.036 | 0.018 | Negligible | Asian | 3.52 | NS | NS | NS | NS | NS | NS | NS | NS |
eortc09 | 9. Have you had pain? | Pain | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
eortc19 | 19. Did pain interfere with your daily activities? | Pain | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS | NS |
Longitudinal DIF comparisons
Item no | Item content | Domain | Test of uniform DIF | Test of non-uniform DIF | ||
---|---|---|---|---|---|---|
P-value (group effect) | "Favored" group | Odds Ratio | P-value (on Interaction term) | |||
eortc29 | 29. How would you rate your overall health during the past week? | Global | NS | NS | NS | NS |
eortc30 | 30. How would you rate your overall quality of life during the past week? | Global | NS | NS | NS | NS |
eortc01 | 1. Do you have any trouble doing strenuous activities, like carrying a heavy shopping bag or a suitcase? | Physical | p = .001 | Non-Asian | 0.43 | NS |
eortc02 | 2. Do you have any trouble taking a long walk? | Physical | p = .005 | Asian | 2.13 | NS |
eortc03 | 3. Do you have any trouble taking a short walk outside of the house? | Physical | NS | NS | NS | NS |
eortc04 | 4. Do you need to stay in bed or a chair during the day? | Physical | NS | NS | NS | NS |
eortc05 | 5. Do you need help with eating, dressing, washing yourself or using the toilet? | Physical | NS | NS | NS | NS |
eortc06 | 6. Were you limited in doing either your work or other daily activities? | Role | NS | NS | NS | NS |
eortc07 | 7. Were you limited in pursuing your hobbies or other leisure time activities? | Role | NS | NS | NS | NS |
eortc21 | 21. Did you feel tense? | Emotional | p = .001 | Non-Asian | 0.44 | p = .011 |
eortc22 | 22. Did you worry? | Emotional | NS | NS | NS | NS |
eortc23 | 23. Did you feel irritable? | Emotional | NS | NS | NS | p = .035 |
eortc24 | 24. Did you feel depressed? | Emotional | p < .001 | Asian | 3.21 | p < .001 |
eortc20 | 20. Have you had difficulty in concentrating on things, like reading a newspaper or watching television? | Cognitive | p = .001 | Non-Asian | 0.36 | NS |
eortc25 | 25. Have you had difficulty remembering things? | Cognitive | p < .001 | Asian | 3.53 | NS |
eortc26 | 26. Has your physical condition or medical treatment interfered with your family life? | Social | NS | NS | NS | NS |
eortc27 | 27. Has your physical condition or medical treatment interfered with your social activities? | Social | NS | NS | NS | NS |
eortc10 | 10. Did you need to rest? | Fatigue | NS | NS | NS | NS |
eortc12 | 12. Have you felt weak? | Fatigue | p = .002 | Asian | 2.20 | NS |
eortc18 | 18. Were you tired? | Fatigue | p = .001 | Non-Asian | 0.50 | NS |
eortc14 | 14. Have you felt nauseated? | Nausea | NS | NS | NS | NS |
eortc15 | 15. Have you vomited? | Nausea | NS | NS | NS | NS |
eortc09 | 9. Have you had pain? | Pain | NS | NS | NS | NS |
eortc19 | 19. Did pain interfere with your daily activities? | Pain | NS | NS | NS | NS |