Variable | Category | Positive/examined | %* | Wald’s Chi-square | β ± SE | OR | 95% CI | P-value |
---|---|---|---|---|---|---|---|---|
Origin | Â | Â | Â | 2.201 | Â | Â | Â | 0.138 |
Central Italy | 56/365 | 15.3 | 5.249 | 1.835 ± 0.8011 | 6.268 | 1.304–30.132 | 0.022 | |
Northern Italy | 36/295 | 12.2 | Â | 0 | 1 | Â | Â | |
Altitude (m.a.s.l.) | Â | Â | Â | 6.248 | Â | Â | Â | 0.044 |
 < 200 | 18/147 | 12.2 | 3.980 | 1.553 ± 0.7786 | 4.727 | 1.028–21.746 | 0.046 | |
200–500 | 31/172 | 18 | 10.391 | 2.437 ± 0.7560 | 11.440 | 2.599–50.347 | 0.001 | |
 > 500 | 11/145 | 7.6 |  | 0 | 1 |  |  | |
Origin × altitude (m.a.s.l.) |  |  |  | 9.257 |  |  |  | 0.010 |
Central Italy ×  < 200 | 6/36 | 16.7ab | 1.905 | − 1.335 ± 0.9671 | 0.263 | 0.040–1.752 | 0.168 | |
Central Italy × 200–500 | 9/75 | 12.0b | 8.185 | − 2.601 ± 0.9093 | 0.074 | 0.012–0.441 | 0.004 | |
Central Italy ×  > 500 | 9/65 | 13.8b |  | 0 | 1 |  |  | |
Northern Italy ×  < 200 | 12/111 | 10.8a |  | 0 | 1 |  |  | |
Northern Italy × 200–500 | 22/97 | 22.7b |  | 0 | 1 |  |  | |
Northern Italy ×  > 500 | 2/80 | 2.5 |  | 0 | 1 |  |  |