Estimates from analyses considering the air pollution concentrations as continuous variables are given in table 2. Regression coefficients are expressed for increases from the 5th to the 95th percentile of each pollutant, and direct comparisons between the estimates are possible. Similar effects were detected for concentrations of SO2 and total suspended particulates on the same day as well as for levels of the air pollutants on previous days. Effect estimates for 5-day moving averages were comparable in magnitude. In analyses that excluded the 1985 air pollution episode, an increase of 70 ng of SO2 per m3 (5th to 95th percentile) was associated with an increase in heart rate of 1.75 beats per minute (95 percent confidence interval: 0.93, 2.57), and an increase of 75 lg of total suspended particulates per m3 (5th to 95th percentile) was associated with an increase in heart rate of 1.12 beats per minute (95 percent confidence interval: 0.35, 1.90). The estimate for CO was exactly the same, with only the lower bound of the confidence interval just crossing zero.