Table 3.
The association of combined socioeconomic status with low back pain after multiple data imputations (n = 26,037. Poisson regression analysis)
| Socioeconomic status | Model A | Model B | Model C | |||
|---|---|---|---|---|---|---|
| PR | 95% CI | PR | 95% CI | PR | 95% CI | |
| Fixed effect parameters | ||||||
| Educational attainment, years (ref, ≥13) | ||||||
| 10–12 | 1.03 | 0.98, 1.08 | – | – | 1.01 | 0.97, 1.06 |
| < 10 | 1.05 | 1.002, 1.11 | – | – | 1.02 | 0.97, 1.08 |
| Past occupation (ref, professionals) | ||||||
| White-collared workers | 1.01 | 0.95, 1.06 | – | – | 1.01 | 0.96, 1.07 |
| Blue-collared workers | 1.05 | 0.99, 1.10 | – | – | 1.03 | 0.97, 1.08 |
| Never worked before | 1.02 | 0.94, 1.11 | – | – | 1.00 | 0.92, 1.08 |
| Income, yen (ref, ≥3 million) | ||||||
| 2 million–2.99 million | – | – | 1.00 | 0.95, 1.06 | 1.00 | 0.95, 1.06 |
| 1 million–1.99 million | – | – | 1.02 | 0.96, 1.07 | 1.02 | 0.96, 1.08 |
| < 1 million | – | – | 1.06 | 0.99, 1.13 | 1.06 | 0.99, 1.14 |
| Subjective economic situation (ref, very comfortable) | ||||||
| Comfortable | – | – | 1.04 | 0.97, 1.11 | 1.04 | 0.97, 1.11 |
| Difficult | – | – | 1.12 | 1.04, 1.20 | 1.15 | 1.07, 1.24 |
| Very difficult | – | – | 1.17 | 1.07, 1.29 | 1.27 | 1.15, 1.39 |
| Wealth, yen (ref, ≥50 million) | ||||||
| 10 million–49.99 million | – | – | 1.01 | 0.95, 1.07 | 1.00 | 0.94, 1.06 |
| 5 million–9.99 million | – | – | 0.99 | 0.93, 1.07 | 0.99 | 0.92, 1.06 |
| 1 million–4.99 million | – | – | 1.01 | 0.94, 1.09 | 1.00 | 0.93, 1.08 |
| < 1 million | – | – | 1.03 | 0.95, 1.12 | 0.99 | 0.95, 1.11 |
| Random parameter | ||||||
| Municipality level variance (standard error) | 0.001 (< 0.001) | 0.001 (< 0.001) | 0.001 (< 0.001) | |||
Abbreviations: PR prevalence ratio, 95% CI 95% credible interval
Model A, educational attainment and past occupation concurrently added to the model adjusting for age, sex, number of persons living together, marital status, musculoskeletal disease, BMI, drinking habit, smoking and physical activity
Model B, income, subjective economic situation, wealth concurrently added to the model adjusting for age, sex, number of persons living together, marital status, musculoskeletal disease, BMI, drinking habit, smoking and physical activity
Model C, all socioeconomic status concurrently added to the model adjusting for age, sex, number of persons living together, marital status, musculoskeletal disease, BMI, drinking habit, smoking and physical activity