Table II.
Mixed logistic regression model evaluating the effect of treatment group (twice-daily versus three-times-daily milking) on the probability of lameness (VLS > 2). The variable “cow id” was added to the model as a random effect
| Variables | n | Lame at enrollment | Lame at 30 days | Lame at 60 days | Lame at 90 days | Adjusted odds ratio | P-value |
|---|---|---|---|---|---|---|---|
| Three times daily | 261 | 100% | 64% | 56% | 47% | 1.36 | 0.006 |
| Twice daily | 219 | 100% | 63% | 51% | 38% | Ref. | |
| Parity = 1 | 30 | 100% | 57% | 40% | 10% | Ref. | 0.01 |
| Parity = 2 | 205 | 100% | 43% | 38% | 23% | 0.94 | |
| Parity > 2 | 245 | 100% | 52% | 44% | 31% | 1.32 |
Ref. — value of lameness in the reference group.