Table 3. Weighted frequencies and risk ratios associated with tick activity observed on dogs as part of the End-of-Phase evaluation in 2013.* .
| Dogs with ticks | Dogs without ticks | Risk ratio (95% CI) | |
| Seresto collar | |||
| No Seresto collar observed | 85.5% (73, 98) | 42.5% (34, 51) | 5.4 (4.0, 7.5) |
| Seresto collar observed | 15.5% (2, 27) | 57.5% (49, 66) | ref |
| Number of dogs | |||
| Greater than 2 dogs | 46.3% (28, 65) | 32.1% (25, 40) | 1.6 (1.3, 2.0) |
| Fewer than 2 dogs | 53.7% (35, 72) | 67.9% (60, 75) | ref |
| Restraint practices | |||
| Always restrain | 19.2% (5, 34) | 36.1% (28, 44) | 0.55 (0.40, 0.74) |
| Never restrain | 41.8% (23, 60) | 28.8% (21, 36) | 1.2 (0.97, 1.5) |
| Sometimes restrain | 38.9% (21, 57) | 35.2% (28, 43) | ref |
*This analysis only relates to homes with at least one dog.