Table 1.
Bivariate logistic regression analysis of risk factors associated with clustering.
| Characteristic | Incidence | Clustered | Non-Clustered | 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) | 1.57 (1.12–2.19) | 0.011 |
| Age * | |||||
| 0 to 14 | 3.1 | 18 (4.2) | 4 (2.0) | 4.61 (1.39–16.84) | 0.004 |
| 15 to 24 | 5.8 | 51 (12.0) | 17 (8.4) | 3.07 (1.58–6.03) | 0.000 |
| 25 to 44 | 10.4 | 170 (39.9) | 47 (23.1) | 3.70 (2.33–5.89) | 0.000 |
| 45 to 64 | 10.7 | 102 (23.9) | 48 (23.6) | 2.17 (1.35–3.52) | 0.000 |
| 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) | 5.82 (3.46–9.54) | 0.000 |
| Foreign-Born | 20 | 75 (17.6) | 116 (57.1) | 0.340 (0.261–0.620) | 0.000 |
| Residence | |||||
| Winnipeg | 9.7 | 235 (55.1) | 153 (75.4) | 1 | |
| other urban | 4.1 | 14 (3.3) | 11 (5.4) | 0.829 (0.369–1.829) | 0.809 |
| reserves | 33.7 | 148 (34.7) | 15 (7.4) | 6.424 (3.563–10.947) | 0.000 |
| other rural | 9.2 | 29 (6.9) | 24 (11.8) | 0.787 (0.443–1.392) | 0.051 |
| Site of Infection | |||||
| Extrapulmonary | 111 (26.1) | 66 (32.5) | 1 | ||
| Pulmonary | 315 (73.9) | 137 (67.5) | 1.367 (0.951–1.969) | 0.112 | |
* χ2 test for overall linear trend in age = 32.6, p < 0.001