This study had a number of limitations that should be considered when interpreting the data. Firstly, the target population; those affected by EI, is a complex, disparate, and unknown population and therefore it is difficult to comment accurately on the representativeness of the sample. All horse owners in Australia are not registered on a centralized database, or otherwise controlled, and as a result, it is not possible to know how extensive the database used to access horse owners (the HECD) was. However, at a national cross-industry sector level it is believed that this was the most extensive and efficient online route to access the target population, and the use of the database as a central communication facility during the EI crisis meant that this was likely to have been a focus for those affected during the epidemic.