Volume 14, Number 5—May 2008
Dispatch
Lakes as Source of Cholera Outbreaks, Democratic Republic of Congo
Table
Model parameters and odds ratios of the negative binomial model selected for cholera cases in Katanga and Eastern Kasai, Democratic Republic of the Congo, 2000–2005*
| Characteristic | Coefficient estimate | Standard error | t value | Pr(>|t|) | Odds ratio | 95% CI |
|---|---|---|---|---|---|---|
| Intercept | 5.50 | 1.04 | 5.27 | 8.92 × 10−7 | ||
| Ln (area) | −0.28 | 0.11 | −2.44 | 1.64 × 10−2 | ||
| Population | 1.97 × 10−6 | 1.17 × 10−6 | 1.69 | 9.46 × 10−2 | ||
| Railway station | 0.61 | 0.25 | 2.42 | 1.74 × 10−2 | 1.8 | 1.12–3.02 |
| Harbor | 1.39 | 0.33 | 4.16 | 7.06 × 10−5 | 4.0 | 2.09–7.75 |
| Main road | 1.43 | 0.41 | 3.50 | 7.09 × 10−4 | 4.2 | 1.88–9.32 |
| Lake | 2.01 | 0.33 | 6.12 | 2.20 × 10−8 | 7.5 | 3.92–14.23 |
*Coefficient estimate, regression coefficients (for discrete variables, their exponential gives the odds ratio); t value, value of the t distribution; Pr(>|t|), probability of the null hypothesis of a coefficient estimate not statistically different from zero; CI, confidence interval; intercept, average number of cases; Ln, natural logarithm.


