FIGURE 3.
Annual (July 1–June 30) estimates of the association of influenza-like illness (ILI) incidence with (a) respiratory hospitalization incidence in all age groups and (b) respiratory mortality incidence for individuals aged 20–64 years and individuals 65 years or older: the Netherlands, 1999–2005.
Note. The horizontal line in each chart gives the value of an ILI regression coefficient that is constant in time, as an indication of the average value of the ILI regression coefficients over the study period. The 95% confidence intervals for the regression coefficients are presented in the figure as well.