Table 2.
Multivariate logistic regression analysis of risk factors associated with clustering
| Characteristic | Incidence | Clustered | Non-Clustered (unique) | Odds Ratio | p value |
| (person-year/100 000) | n = 426 (%) | n = 203 (%) | (95%) CI | ||
| Sex | |||||
| Female | 8.4 | 167 (39.2) | 102 (50.2) | 1 (reference) | |
| Male | 10.1 | 259 (60.8) | 101 (49.8) | 1.959 (1.306–2.938) | 0.0011 |
| Age * | |||||
| 0 to 14 | 3.1 | 18 (4.2) | 4 (2.0) | 2.55 (0.74–8.88) | 0.1401 |
| 15 to 24 | 5.8 | 51 (12.0) | 17 (8.4) | 2.53 (1.20–5.34) | 0.0151 |
| 25 to 44 | 10.4 | 170 (39.9) | 47 (23.1) | 3.26 (1.92–5.54) | 0.0000 |
| 45 to 64 | 10.7 | 102 (23.9) | 48 (23.6) | 1.47 (0.87–2.50) | 0.1523 |
| 65 + | 18.4 | 85 (20.0) | 87 (42.9) | 1 | |
| Origin† | |||||
| Canadian-Born (non-treaty) | 3.3 | 97 (22.8) | 60 (29.6) | 1 | |
| Canadian-Born (treaty) | 48.4 | 254 (59.6) | 27 (13.3) | 4.108 (2.163–7.803) | 0.0000 |
| Foreign-Born | 20.0 | 75 (17.6) | 116 (57.1) | 0.248 (0.149–0.412) | 0.0000 |
| Residence‡ | |||||
| Winnipeg | 9.7 | 235 (55.1) | 153 (75.4) | 1 | |
| other urban | 4.1 | 14 (3.3) | 11 (5.4) | 0.490 (0.195–1.230) | 0.1289 |
| reserves | 33.7 | 148 (34.7) | 15 (7.4) | 1.206 (0.546–2.665) | 0.6433 |
| other rural | 9.2 | 29 (6.9) | 24 (11.8) | 0.410 (0.203–0.830) | 0.0132 |
* age overall effect, χ2 test = 21.83 with 4 different factors, p < 0.001 † origin overall effect, χ2 test = 81.54 with 2 different factors, p < 0.001 ‡ residence overall effect, χ2 test = 9.26 with 3 different factors, p < 0.05