Correlation coefficients for the mean long-term seasonal (summer and winter) concentration of exposure variables 1994–1997
| Temperature | NO2 | SO2 | O3 | |
| Winter# | ||||
| PM10 | −0.106 | 0.595 | 0.52 | −0.581 |
| O3 | −0.345 | −0.839 | 0.146 | |
| SO2 | −0.519 | −0.129 | ||
| NO2 | 0.388 | |||
| Temperature | NO2 | SO2 | O3 | |
| Summer¶ | ||||
| PM10 | 0.607 | 0.412 | 0.335 | −0.429 |
| O3 | −0.428 | −0.625 | −0.204 | |
| SO2 | 0.414 | −0.144 | ||
| NO2 | 0.383 |
NO2: nitrogen dioxide
O3: ozone
SO2: sulphur dioxide
PM10: particulate matter <10 µm in diameter
#: mean between lung-function tests in autumn and spring 1994–1997
¶: mean between lung-function tests in spring and autumn 1994–1997