|
Contributions of the variables to baseline SF-36 Mental Health scores |
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| Correlation (r) with |
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|
|
||||||
| Quantitative variables |
Mean |
STD |
Baseline SF36-MH |
R2 |
p-value |
|
|
|
||||||
| Baseline bodily pain |
3.67 |
1.12 |
-0.36 |
0.130 |
<0.0001 |
|
| Age |
41.8 |
10.6 |
0.15 |
0.023 |
0.0121 |
|
|
|
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| Baseline SF36-MH |
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| Categorical variables |
Category |
n |
Mean |
STD |
||
|
|
||||||
| Sex |
Male |
166 |
61.25 |
19.88 |
0.002 |
0.5065 |
| Female |
110 |
62.95 |
19.35 |
|||
| Workers' compensation |
Yes |
105 |
56.15 |
20.53 |
0.052 |
0.0001 |
| No |
171 |
65.47 |
18.27 |
|||
| Length of episode |
<=6 week |
54 |
68.52 |
18.99 |
0.033 |
0.0109 |
| 6–26 weeks |
133 |
61.29 |
17.95 |
|||
| >26 weeks |
89 |
58.88 |
21.68 |
0.006 |
0.2024 |
|
| Comorbid illnesses |
Yes |
69 |
59.36 |
19.81 |
||
| No |
207 |
62.78 |
19.58 |
|||
|
|
||||||
| R2 from the model including all above variables |
0.227 |
|||||
|
Note: R2 was calculated using the model including only one variable. SF-36 MH scores range from 0–100, where 100 means "always happy and calm over past month." 280 (surgical+ non-surgical) patients have DNA, four patients, 3 missing baseline SF36-MH and 1 missing baseline bodily pain, were dropped from analysis In covariate selection, linear regression with backward selection method (p = 0.1) was applied, where baseline Sf36-MH was dependent variables, age, sex, workers' compensation, baseline bodily pain, comorbid illnesses, patient group (nonsurgical vs. surgical), marital status, education, and prior episodes were independent variables, and age, sex and workers' compensation were fixed in the model | ||||||
Max et al. Molecular Pain 2006 2:14 doi:10.1186/1744-8069-2-14 |
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