Table 3.
Cross-sectional and longitudinal prediction of non-specific side effects with sequential multiple regression analyses
| Baseline Predictors | Unadjusted effect |
Model 1 R2 = .16** |
Model 2 R2 =.20** |
Model 3 R2 = .25** |
|---|---|---|---|---|
| Criterion: Side effects at baseline | r | rp | rp | rp |
| Age | −.21* | - | - | −.18 |
| Gender | −.14 | - | - | −.09 |
| Arthritis symptoms (RASQ) | .15 | - | - | .10 |
| Depression (MHI) | −.06 | - | - | −.10 |
| Anxiety (MHI) | −.03 | - | - | −.01 |
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| Symptomatic drugs | −.02 | - | −.06 | −.10 |
| Steroids | .14 | - | .09 | .08 |
| DMARDs | −.04 | - | .06 | .01 |
| Biologic response modifiers | .19# | - | .14 | .10 |
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| Erytrocyte sedimentation rate | .08 | .11 | .11 | .11 |
| Swollen joints count | .10 | .02 | .01 | −.06 |
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| BMQ Specific Concern | .39** | .39** | .39** | .37** |
| ΔR2 for BMQ Specific Concern | - | .15** | .14** | .12** |
| Baseline Predictors | Unadjusted effect |
Model 1 R2= .11** |
Model 2 R2= .14** |
Model 3 R2= .28** |
|---|---|---|---|---|
| Criterion: Side effects at 6-months follow-up |
r | rp | rp | rp |
| Age | −.42** | - | - | −.34** |
| Gender | −.10 | - | - | −.04 |
| Arthritis symptoms (RASQ) | .03 | - | - | .06 |
| Depression (MHI) | .18# | - | - | .03 |
| Anxiety (MHI) | .19# | - | - | .12 |
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| Symptomatic drugs | .02 | - | −.01 | −.003 |
| Steroids | .15 | - | .12 | .13 |
| DMARDs | .05 | - | .11 | .04 |
| Biologic response modifiers | .07 | - | .04 | .05 |
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| Erytrocyte sedimentation rate | .04 | .07 | .06 | .06 |
| Swollen joints count | .10 | .04 | .02 | −.03 |
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| BMQ Specific Concern | .32** | .32** | .34** | .25** |
| ΔR2 for BMQ Specific Concern | - | .10** | .11** | .05** |
Note. Model 1: adjusted for disease activity (i.e., Erytrocyte sedimentation rate, swollen joints count); Model 2: adjusted for disease activity, and medication (i.e., Symptomatic drugs, Steroids, DMARDs, Biologic response modifiers); Model 3: adjusted for disease activity, medication, demographics (i.e., age, gender), and symptoms (i.e., RASQ, depression, anxiety).
RASQ = Rheumatoid arthritis symptom questionnaire; MHI = Mental health inventory; DMARDs = Disease-modifying anti-rheumatic drugs; BMQ = Beliefs about Medicines Questionnaire
Dummy codes entered for gender (1 = female; 2 = male).
rp = partial correlation coefficients, adjusting for all variables in the respective model
p<0.10
p<0.05
p<0.01
ΔR2 = change in explained variance through integration of BMQ specific concerns with significance of F change; R2 = Cumulative amount of explained variance through all predictors in the model.