Association of covariates with pandemic influenza mortality rates.

1Statistics were obtained from EUROSTAT. Data on per capita government expenditure on health was derived from the World Health Information Statistical Information System (WHOSIS).2Random-effects poisson regression model.3Total emissions in CO2 equivalents presented as indices, with the base year = 100.4Population weighted annual mean concentration of particulate matter at urban background stations in agglomerations.5Expressed in international dollars, which are calculated using purchasing power parities (PPP) (PPP - rates of currency conversion constructed to account for differences in price level between countries).6Index of inequality of income distribution ranging from 0 (complete equality) to 100 (complete inequality).7The index is calculated from Purchasing Power Standards (PPS) figures and expressed with respect to European Union-27 = 100.8The ratio between the total number of persons of aged 65 and over, and the number of persons aged between 15 and 64.