Table 3.
Analysis of influence of season of birth (Q1 to Q4) on hip fracture rates, assessed by multiple linear regression after ln transformation.
| Exp(B) | p | |
|---|---|---|
| WOMEN | ||
| Q1 | 1 | Reference |
| Q2 | 1.04(1.00–1.07) | 0.04 |
| Q3 | 1.04(1.00–1.08) | 0.04 |
| Q4 | 1.02 (0.98–1.06) | 0.29 |
| MEN | ||
| Q1 | 1 | Reference |
| Q2 | 1.03 (0.99–1.09) | 0.18 |
| Q3 | 1.03 (0.98–1.08) | 0.26 |
| Q4 | 1.08 (1.03–1.13) | 0.003 |
Three dummy variables were formed to capture differences in rates between quarters of birth year with Q1 as reference. Results were mutually adjusted and controlled for age and outcome year.