Figure 2
Odds ratio (OR) for emergency respiratory symptoms calls according to various lag times, Palermo, Sicily, 2005-2007. Lag 0 is for pollutant concentrations averaged on the day of the call, lag 1 is for pollutant concentrations averaged for the previous day of the call, and so on. Associations are expressed as adjusted OR [95% confidence interval (CI)] in relation to an increase of 10 μg/m3 of selected air pollutants (CO: an increase of 1 mg/m3). ORs adjusted for meteo-climatic parameters, and influenza epidemic peaks (see Methods - Statistical analysis).