(a) Relative infection ratios; and (b) relative hospitalization ratios for First Nations (FN) and non-First Nations (non-FN) age groups: Manitoba, Canada; Spring wave of the 2009 H1N1 pandemic. For Relative infection (hospitalization) ratios, bar plots and 95% confidence intervals correspond to the age-standardized ratio of the proportion of infectious (hospitalized) cases in a given age group to the proportion of the population in the same age group . A relative ratio higher than 1 indicates that the corresponding age group experienced a higher incidence of infection or hospitalization than the population as a whole.
Richardson et al. BMC Public Health 2012 12:1098 doi:10.1186/1471-2458-12-1098