Direct logistic regression was performed to assess the impact of a number of factors on the likelihood that respondents had been vaccinated in the previous season. The model contained five independent Table 3 , only two of the independent variables made a unique statistically significant contribution to the model (knowledge score and risk perception score). The strongest predictor of vaccination status was the risk perception score, recording an odds ratio of 1 . 76, indicating that respondents who had higher risk perception scores were >1 . 76 times more likely to have been vaccinated in the last 12 months than those with lower scores, controlling for all other factors in the model. Knowledge score with an odds ratio of 1 . 05 indicated that knowledgeable respondents were more likely to be vaccinated than the unknowledgeable, controlling for other factors in the model.