Table 1.
Bivariate and multivariate analysis of factors associated with previous exposure to Bacillus anthracis
| Variable | Positive (n) | Total (N) | % Positive (95% CI) | Unadjusted OR (95% CI) | P value | G P value | AOR (95% CI) | M P value |
|---|---|---|---|---|---|---|---|---|
| Residence | ||||||||
| Rural | 110 | 784 | 11.2 (7.8–14.6) | 1.0 (0.5–2.0) | 0.902 | 0.902 | – | – |
| Urban | 31 | 307 | 11.6 (5.2–18.1) | REF | – | – | REF | – |
| Sex | ||||||||
| Male | 61 | 430 | 13.6 (7.8–19.4) | 1.4 (0.8–2.5) | 0.2139 | 0.2139 | – | – |
| Female | 80 | 661 | 9.9 (6.8–13.0) | REF | – | – | REF | – |
| Age (in years) | ||||||||
| 15–29 | 67 | 529 | 11.0 (7.5–14.6) | REF | – | – | REF | – |
| 30–49 | 54 | 395 | 11.4 (5.4–17.4) | 1.0 (0.5–2.0) | 0.9228 | – | – | – |
| 50–64 | 20 | 167 | 12.2 (5.8–18.5) | 1.12 (0.6–2.2) | 0.7571 | 0.9532 | – | – |
| Education level | ||||||||
| No primary | 22 | 223 | 7.0 (2.4–11.6) | REF | – | – | REF | – |
| Some primary | 47 | 295 | 14.5 (10.1–18.9) | 2.3 (1.07–4.76) | 0.0322* | 0.1007 | 0.91 (0.5–1.67) | 0.7693 |
| Complete primary and secondary+ | 72 | 573 | 11.9 (7.7–16.1) | 1.8 (0.9–3.8) | 0.1236 | – | 1.16 (0.56–2.4) | 0.6883 |
| Wealth quintiles | ||||||||
| Lowest | 33 | 234 | 10.7 (5.9–15.6) | 1.99 (0.85–4.66) | 0.1145 | – | 4.91 (1.57–15.4) | 0.0063* |
| Second | 44 | 189 | 17.1 (7.0–27.2) | 3.42 (1.26–9.28) | 0.016* | 0.0622 | 5.57 (1.77–17.51) | 0.0033* |
| Middle | 23 | 188 | 9.1 (5.1–13.0) | 1.65 (0.71–3.83) | 0.2466 | – | 2.0 (0.64–6.19) | 0.2312 |
| Fourth | 22 | 186 | 18.5 (6.8–30.3) | 3.77 (1.26–11.30) | 0.018* | – | 4.56 (1.15–18.14) | 0.0313* |
| Highest | 19 | 294 | 5.7 (2.0–9.4) | REF | – | – | REF | – |
| Province | ||||||||
| Nairobi | 9 | 153 | 9.5 (1.5–17.6) | 5.46 (1.20–24.88) | 0.0281* | – | 18.27 (2.84–117.39) | 0.0022* |
| Central | 10 | 150 | 6.4 (2.5–10.3) | 3.55 (0.91–13.86) | 0.0679 | – | 6.48 (1.34–31.36) | 0.0203* |
| Coast | 20 | 129 | 12.8 (6.1–19.5) | 7.63 (2.01–29.04) | 0.0029* | – | 13.39 (3.09–57.9) | 0.0005* |
| Eastern | 11 | 112 | 7.3 (2.0–12.7) | 4.11 (0.98–17.24) | 0.0531 | – | 5.83 (1.24–27.35) | 0.0253* |
| North Eastern | 7 | 140 | 1.9 (0.0–4.1) | REF | – | – | REF | – |
| Nyanza | 35 | 154 | 21.4 (13.3–29.4) | 14.09 (3.88–51.14) | < 0.0001* | – | 18.19 (4.41–74.91) | < 0.0001* |
| Rift Valley | 10 | 117 | 11.0 (1.3–20.8) | 6.44 (1.36–30.48) | 0.019* | – | 10.55 (2.32–48.03) | 0.0023* |
| Western | 39 | 136 | 27.5 (18.4–36.7) | 19.71 (5.49–70.84) | < 0.0001* | < 0.0001* | 25.41 (6.4–100.92) | < 0.0001* |
AOR = adjusted odds ratio; CI = confidence interval; REF = reference.
P value is the category P value, G P value is the global P value for the bivariate variable, M P value is the category multivariate P value.
*
Bold values have significant P values.