Table 3.
Hierarchical linear models for shoulder abduction and shoulder flexion ROM (degrees)
| Abduction | Coefficient (SE) | |
|---|---|---|
|
| ||
| Variables | Unconditional Model | Final Model |
| Fixed effects | ||
| Intercept | 128.20 (1.56) b | 127.97 (1.21) b |
| Time a (linear rate of change) | 7.76 (0.80) b | 7.96 (0.71) b |
| Time a (quadratic rate of change) | −1.40 (0.16) b | −1.44 (0.15) b |
| Time a (cubic rate of change) | 0.07 (0.01) b | 0.08 (0.01) b |
| Time invariant covariates | ||
| Intercept | ||
| Ethnicity (Non-white) | −6.66 (1.73) b | |
| Neoadjuvant chemotherapy | −5.28 (2.26) c | |
| Type of surgery | −30.54 (3.10) b | |
| Axillary dissection | −11.32 (2.64) b | |
| Shoulder abduction (pre-operative, affected side) | 0.64 (0.04) b | |
| Linear | ||
| Lived alone at enrollment | 3.86 (1.35) c | |
| Type of surgery | 15.01 (1.83) b | |
| Axillary dissection | 3.45 (1.51) c | |
| Adjuvant chemotherapy during 1styear | 3.71 (1.23) c | |
| Quadratic | ||
| Lived alone at enrollment | −0.94 (0.32) c | |
| Type of surgery | −2.38 (0.39) b | |
| Axillary dissection | −0.66 (0.32) c | |
| Adjuvant chemotherapy during 1st year | −0.86 (0.30) c | |
| Cubic | ||
| Lived alone at enrollment | 0.05 (0.02) c | |
| Type of surgery | 0.11 (0.02) b | |
| Axillary dissection | 0.04 (0.02) c | |
| Adjuvant chemotherapy during 1st year | 0.05 (0.02) c | |
| Variance components | ||
| In intercept | 815.74 b | 435.74 b |
| In linear rate | 142.21 b | 90.38 b |
| In quadratic fit | 5.07 b | 3.41 b |
| In cubic fit | 0.01 b | 0.01 b |
| Goodness-of-fit deviance (parameters estimated) | 26350.367 (15) | 25981.557 (32) |
| Model comparison χ2 (df) | 368.81 (17) b | |
| Flexion | Coefficient (SE) | |
|---|---|---|
|
| ||
| Variables | Unconditional Model | Final Model |
| Fixed effects | ||
| Intercept | 154.56 (0.98) b | 154.49 (0.78) b |
| Time a (linear rate of change) | 4.50 (0.48) b | 4.53 (0.43) b |
| Time a (quadratic rate of change) | −0.76 (0.10) b | −0.77 (0.09) b |
| Time a (cubic rate of change) | 0.04 (0.01) b | 0.04 (0.01) b |
| Time invariant covariates | ||
| Intercept | ||
| Years of education | 0.37 (0.17) c | |
| Exercised preoperatively | 3.02 (0.91) b | |
| Neoadjuvant chemotherapy | −3.23 (1.16) c | |
| Breast pain functional interference score | −1.67 (0.46) b | |
| Axillary dissection | −2.19 (1.03) c | |
| Surgical drain placed | −14.72 (1.64) b | |
| Shoulder flexion (pre-operative, affected side) | 0.61 (0.04) b | |
| Linear | ||
| Lived alone at enrollment | 1.89 (0.77) c | |
| Type of surgery | 2.82 (0.99) c | |
| Surgical drain placed | 5.35 (1.01) b | |
| Adjuvant chemotherapy during 1st year | 1.88 (0.71) c | |
| Quadratic | ||
| Lived alone at enrollment | −0.44 (0.19) c | |
| Type of surgery | −0.67 (0.25) c | |
| Surgical drain placed | −0.67 (0.22) c | |
| Adjuvant chemotherapy during 1st year | −0.45 (0.18) c | |
| Cubic | ||
| Lived alone at enrollment | 0.03 (0.01) c | |
| Type of surgery | 0.04 (0.02) c | |
| Surgical drain placed | 0.03 (0.01) c | |
| Adjuvant chemotherapy during 1st year | 0.02 (0.01) c | |
| Variance components | ||
| In intercept | 321.92 b | 185.43 b |
| In linear rate | 49.24 b | 33.70 b |
| In quadratic fit | 1.59 b | 1.17 b |
| In cubic fit | 0.004 b | 0.003 b |
| Goodness-of-fit deviance (parameters estimated) | 23226.56 (15) | 22862.41 (24) |
| Model comparison χ2 (df) | 364.15 (19) b | |
a
Time was coded 0 for initial visit post operative visit;
b
p < 0.001;
c
p < 0.05
df: degrees of freedom; SE: standard error