A, ClonalFrame tree of <i>C. coli</i> by host (brown – cattle, green – sheep, pink – pigs, yellow – chicken and red – human clinical.

<p>B, probabilistic assignment of the host of human <i>C. coli</i> infections using structure attribution model (four equal sized columns would be expected in the absence of any genetic differentiation by host). C, Simpson’s index of diversity by host.</p

Results of the logistic regression for the case-case studies.

<p>(A) Odd ratios and their associated P–value for all the selected cases in the univariate models. Factors with P<0.05 are considered as significant (*). Factors with a P<0.25 are entered in the multivariate model (†).</p><p>(B) Odd ratios and p-values for the final multivariate models. Previous steps, consisting in removing one by one the factors with the highest p-Value at each step, are not shown. The program used to execute the analysis gave P = 0.0060 for the overall model fit for the chicken versus non chicken case-case study, and P = 0.0006 for the <i>C. coli</i> versus <i>C. jejuni</i> case-case study. Because gender is the only factor kept at the end of the multivariate model in the chicken versus non chicken study, odd ratio and P-Value are the same as in the univariate gender model.</p>a<p>Animals are grouped into four density groups (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0064504#pone.0064504.s001" target="_blank">File S1</a>) and the odds ratio indicates the relative amount by which the odds of the outcome changes when the value of the predictor value is increased by 1.0 unit.</p