Table 3.
Estimated effects of breast cancer therapies on EORTC QLQ-BR23 body image score (modified after Afshar-Bakshloo et al. 2022 [51] )
| Estimate | SE | 95%-CI | DF | t-value | p-value | R2a | 95%-CI | |||
|---|---|---|---|---|---|---|---|---|---|---|
| Lower | Upper | Lower | Upper | |||||||
| Intercept | 73.7998 | 9.6102 | 54.9445 | 92.6551 | 1157 | 7.6794 | ≤ 0.0001 | 25.1 | 22.3 | 29.6 |
| Main effects (Estimate = a single change in score value at the time of reference breast surgery) | ||||||||||
| Breast-conserving surgery | -5.259 | 1.8779 | -8.9435 | -1.5746 | 1157 | -2.8005 | 0.0052 | 0.4 | 0 | 1.3 |
| Mastectomy alone | -18.8421 | 4.3314 | -27.3403 | -10.3439 | 1157 | -4.3501 | ≤ 0.0001 | 1.5 | 0.5 | 3 |
| Mastectomy with immediate breast reconstruction | -6.9666 | 2.6312 | -12.1291 | -1.8042 | 1157 | -2.6477 | 0.0082 | 0.5 | 0 | 1.5 |
| Re-operation (more invasive) | -13.8644 | 5.3756 | -24.4115 | -3.3173 | 1157 | -2.5791 | 0.01 | 0.4 | 0 | 1.4 |
| Chemotherapy | -21.6337 | 1.9169 | -25.3946 | -17.8728 | 1157 | -11.286 | ≤ 0.0001 | 12.5 | 9.6 | 15.8 |
| Radiotherapy | 5.3783 | 1.8565 | 1.7358 | 9.0207 | 1157 | 2.897 | 0.0038 | 0.5 | 0 | 1.5 |
| Endocrine therapy | -3.1082 | 1.8629 | -6.7632 | 0.5469 | 1157 | -1.6684 | 0.0955 | 0.2 | 0 | 0.9 |
| Time effect (Estimate = a weekly change in score value caused by the mere influence of time) | ||||||||||
| Time | 0.0017 | 0.1292 | -0.2519 | 0.2552 | 1157 | 0.013 | 0.9897 | 0 | 0 | 0.4 |
| Interaction effects (Estimate = a weekly change in score value caused by the influence of the respective therapy, plus time effect) | ||||||||||
| Breast-conserving surgery | 0.1037 | 0.1407 | -0.1723 | 0.3798 | 1157 | 0.7373 | 0.4611 | 0 | 0 | 0.5 |
| Mastectomy alone | 0.1444 | 0.1706 | -0.1903 | 0.4792 | 1157 | 0.8464 | 0.3975 | 0.1 | 0 | 0.6 |
| Mastectomy with immediate breast reconstruction | -0.0733 | 0.1406 | -0.3491 | 0.2025 | 1157 | -0.5215 | 0.6021 | 0 | 0 | 0.4 |
| Re-operation (more invasive) | -0.0438 | 0.0994 | -0.2388 | 0.1512 | 1157 | -0.441 | 0.6593 | 0 | 0 | 0.4 |
| Chemotherapy | 0.2803 | 0.0467 | 0.1886 | 0.372 | 1157 | 5.9989 | ≤ 0.0001 | 3.9 | 2.2 | 6.1 |
| Radiotherapy | -0.1062 | 0.0647 | -0.2331 | 0.0207 | 1157 | -1.6418 | 0.1009 | 0.3 | 0 | 1.1 |
| Endocrine therapy | -0.0426 | 0.0518 | -0.1442 | 0.059 | 1157 | -0.8234 | 0.4105 | 0.1 | 0 | 0.6 |
| Covariables (time-independent) | ||||||||||
| Age (at the time of breast surgery) | 0.2449 | 0.1118 | 0.0247 | 0.465 | 258 | 2.1904 | 0.0294 | 1.6 | 0.5 | 3.1 |
| Body-mass-index | -0.3365 | 0.2773 | -0.8825 | 0.2095 | 258 | -1.2137 | 0.226 | 0.5 | 0 | 1.5 |
| Relationship status | 4.8655 | 2.8883 | -0.8222 | 10.5532 | 258 | 1.6845 | 0.0933 | 1.1 | 0.3 | 2.4 |
| Secondary breast cancer | -0.4728 | 3.6463 | -7.6532 | 6.7076 | 258 | -0.1297 | 0.8969 | 0 | 0 | 0.4 |
| pN0 (no lymph node involvement) | 2.1281 | 4.112 | -5.9691 | 10.2254 | 258 | 0.5176 | 0.6052 | 0.1 | 0 | 0.7 |
| pN + (lymph node involvement) | 1.4767 | 4.6855 | -7.7501 | 10.7035 | 258 | 0.3152 | 0.7529 | 0 | 0 | 0.5 |
SE Standard error, CI Confidence interval, DF Degree of freedom
aR2 indicates % of variance in scores explained by statistical model. First table row (Intercept) indicates R2 of model overall, remaining rows indicate partial R2 of respective variables