Table 3 Cumulative effect (RR and 95% CI) of extreme temperature (1st, 2.5th, 97.5th and 99th percentiles) on children’s outpatient visits for respiratory diseases stratified by cold and warm seasons, with respect to the reference of median of daily average temperature at different lag days in Harbin

1st

Lag 0–1

1.02 (0.95, 1.10)

1.00 (0.94, 1.05)

1.08 (0.98, 1.19)

0.58

0.56

Lag 0–6

1.00 (0.91, 1.10)

0.99 (0.93, 1.06)

1.22 (1.06, 1.40)

0.17

0.86

Lag 0–10

1.06 (0.95, 1.17)

0.98 (0.92, 1.05)

1.17 (0.94, 1.47)

1.12

0.26

2.5th

Lag 0–1

1.01 (0.92, 1.10)

1.00 (0.94, 1.06)

1.07 (0.99, 1.16)

0.23

0.82

Lag 0–6

1.00 (0.90, 1.12)

0.99 (0.91, 1.07)

1.17 (1.05, 1.30)

0.23

0.82

Lag 0–10

1.05 (0.93, 1.19)

0.98 (0.90, 1.07)

1.10 (0.97, 1.26)

0.94

0.35

97.5th

Lag 0–1

1.08 (1.02, 1.13)

1.02 (0.94, 1.12)

1.04 (0.96, 1.13)

1.01

0.31

Lag 0–6

1.11 (1.04, 1.18)

0.98 (0.88, 1.10)

1.25 (1.10, 1.41)

1.88

0.06

Lag 0–10

1.09 (1.02, 1.18)

0.98 (0.87, 1.10)

1.45 (1.26, 1.68)

1.61

0.11

99th

Lag 0–1

1.10 (1.03, 1.17)

1.03 (0.93, 1.13)

1.05 (0.96, 1.15)

1.16

0.25

Lag 0–6

1.15 (1.05, 1.26)

0.98 (0.87, 1.12)

1.24 (1.07, 1.43)

1.99

0.04

Lag 0–10

1.12 (1.01, 1.25)

0.98 (0.85, 1.12)

1.44 (1.21, 1.72)

1.65

0.10