Table 1.
Final Cox proportional hazard model of cage mortality following experimental inoculation. (C, control; A, DWV-A; B, DWV-B; M, mixed DWV-A and -B. s.e., standard error; s.d., standard deviation.)
| coefficients |
model testing |
|||||
|---|---|---|---|---|---|---|
| parameters | β | s.e. (β) | Exp. (β)a | χ2 (LRT) | d.f. | p-value |
| fixed variable | ||||||
| treatment | 50.706 | 3 | <0.00001* | |||
| C | 0 | — | 1 | |||
| A | 4.643 | 0.619 | 103.865 | |||
| B | 6.480 | 0.643 | 651.826 | |||
| M | 6.093 | 0.638 | 442.705 | |||
| random variable | s.d. | variance | ||||
| cage | 0.403 | 0.162 | ||||
aEquivalent to the hazard ratio, the instantaneous risk of death for bees in each treatment compared with the baseline treatment level (in this case C). Higher levels of β indicate higher risk of death.