Table 1: The most consistently identified herd-level risk factors for bovine TB.

Herd-level risk factors most consistently identified*

Cattle movement (estimated to contribute <20% in some GB and
Irish studies)
Occurrence of TB on contiguous premises and/or level of TB in
surrounding areas (infection pressure)
Herd size

*It is important to note that epidemiological studies may differ in the variables examined, the exact measures used (in relation to the association with badgers etc.), and the study size and power. Therefore, not all risk factors would be expected to be identified equally across all studies.