Variables | Incidence rate ratios | 95% CIs | P value | |
Age (0–19)*Season (spring) | 1.26 | 1.11 | 1.44 | 0.000 |
Age (20-39)*Season (spring) | 1.07 | 0.94 | 1.21 | 0.305 |
Age (40-59)*Season (spring) | 1.06 | 0.94 | 1.18 | 0.354 |
Age (≥60)*Season spring) | Reference | – | – | – |
Season (spring) | 1.03 | 0.94 | 1.12 | 0.533 |
Season (others) | Reference | – | – | – |
First year of observation | 1.07 | 1.02 | 1.12 | 0.004 |
Second year of observation | 0.97 | 0.92 | 1.02 | 0.199 |
Third year of observation | Reference | – | – | – |
Age (0–19) | 0.94 | 0.88 | 1.00 | 0.062 |
Age (20–39) | 0.98 | 0.92 | 1.05 | 0.603 |
Age (40–59) | 0.99 | 0.93 | 1.04 | 0.638 |
Age (≥60) | Reference | – | – | – |
A*B shows the interaction between A and B.