Table 3 Distribution of the daily number of ER admissions for respiratory diseases and daily concentrations of chemical air pollution and aeroallergens during the study period, according to the potential confounders considered in the analysis^a

Day of the week

 Monday

22.7 ± 10.2

30.4 ± 26.5

47.2 ± 25.1

38.2 ± 27.7

12.7 ± 20.9

 Tuesday

21.4 ± 9.8

30.8 ± 25.4

50.3 ± 24.5

37.8 ± 28.6

14.9 ± 28.8

 Wednesday

20.4 ± 9.6

32.5 ± 25.4

51.0 ± 23.8

38.9 ± 29.2

18.8 ± 38.1

 Thursday

21.6 ± 9.7

35.1 ± 27.8

52.9 ± 25.9

38.9 ± 30.2

15.1 ± 23.0

 Friday

23.4 ± 11.1

33.3 ± 25.0

50.9 ± 24.7

39.9 ± 29.7

17.2 ± 32.1

 Saturday

31.1 ± 12.4

31.5 ± 26.0

45.0 ± 25.1

42.2 ± 29.8

18.2 ± 33.4

 Sunday

32.2 ± 12.8

30.4 ± 27.4

40.9 ± 24.0

41.3 ± 28.5

15.8 ± 27.4

  p

<0.001

0.79

0.002

0.87

0.73

Holidays

 Christmas and Easter

47.6 ± 17.5

25.4 ± 15.2

45.1 ± 27.5

32.0 ± 29.9

1.0 ± 1.9

 3 days before/after Christmas and Easter

34.9 ± 16.3

37.9 ± 21.7

58.6 ± 25.8

25.7 ± 23.7

6.4 ± 15.8

 Other holidays

35.6 ± 15.6

37.4 ± 27.7

49.3 ± 22.7

32.2 ± 30.4

12.6 ± 1.9

 Other days

23.8 ± 10.9

31.6 ± 26.4

48.0 ± 25.0

40.4 ± 29.1

16.6 ± 30.2

 p

<0.001

0.39

0.23

0.02

0.20

Influenza outbreaks

 No

19.9 ± 9.0

22.8 ± 21.0

36.8 ± 16.9

55.2 ± 27.4

23.8 ± 31.9

 Yes

31.0 ± 12.0

43.9 ± 27.5

63.0 ± 25.8

19.9 ± 16.4

6.3 ± 23.0

 p

<0.001

<0.001

<0.001

<0.001

<0.001

 2 weeks around 15 August

13.4 ± 4.71

15.8 ± 5.6

20.7 ± 6.3

66.1 ± 15.4

34.7 ± 28.5

 From 16/7 to 31/8 (except 2 weeks around 15 August)

14.4 ± 5.8

14.5 ± 6.4

26.1 ± 8.5

78.0 ± 19.3

29.1 ± 31.6

 Other days

26.4 ± 11.6

34.5 ± 27.1

52.5 ± 24.5

33.7 ± 26.3

13.4 ± 28.7

 p

<0.001

<0.001

<0.001

<0.001

<0.001

Temperature^b (°C)

 −6.4, 6.4

29.1 ± 11.6

57.3 ± 28.3

78.9 ± 27.6

12.1 ± 8.8

0.8 ± 2.5

 6.5, 12.8

28.1 ± 11.3

31.7 ± 21.5

51.7 ± 15.2

23.3 ± 17.3

10.1 ± 31.9

 12.9, 20.3

24.8 ± 11.5

27.5 ± 23.9

43.4 ± 17.1

41.2 ± 20.2

14.9 ± 21.6

 20.4, 28.5

19.5 ± 8.2

14.9 ± 6.8

29.4 ± 9.5

73.7 ± 18.4

32.5 ± 39.7

 p

<0.001

<0.001

<0.001

<0.001

<0.001

 <1 mm

25.4 ± 11.4

35.5 ± 28.0

51.5 ± 26.2

38.0 ± 33.7

16.0 ± 29.9

 ≥1 mm

25.2 ± 11.5

25.5 ± 19.2

45.0 ± 20.1

33.7 ± 26.0

9.5 ± 27.3

 p

0.87

<0.001

0.01

0.10

0.02

 30.4, 60.4

26.4 ± 10.3

17.8 ± 13.1

41.6 ± 17.9

52.1 ± 24.6

25.1 ± 34.3

 60.5, 68.6

23.1 ± 11.6

25.5 ± 18.9

43.2 ± 22.2

50.9 ± 31.3

21.8 ± 37.5

 68.7, 76.4

25.3 ± 11.3

44.7 ± 30.5

56.9 ± 32.1

28.3 ± 23.0

9.6 ± 25.4

 76.5, 85.5

26.7 ± 12.1

42.5 ± 28.8

58.4 ± 22.1

16.7 ± 15.9

1.9 ± 6.0

 p

0.01

<0.001

<0.001

<0.001

<0.001