The cumulative cold and hot effects of temperature on IHD mortality along the lag days, using 5 degrees of freedom natural cubic spline for temperature and 4 degrees of freedom natural cubic spline for lag
| Relative risk | ||||||
|---|---|---|---|---|---|---|
| Effect | Lag | Beijing | Tianjin | Shanghai | Wuhan | Guangzhou |
| Cold* | 0–2 | 0.94 (0.82, 1.08) | 1.01 (0.92, 1.11) | 1.36 (1.19, 1.56) | 1.08 (0.90, 1.29) | 1.09 (0.92, 1.28) |
| 0–13 | 1.31 (1.09, 1.57) | 1.22 (1.07, 1.39) | 1.47 (1.15, 1.88) | 1.32 (1.09, 1.60) | 1.60 (1.29, 1.98) | |
| 0–20 | 1.42 (1.11, 1.81) | 1.39 (1.18, 1.64) | 1.65 (1.20, 2.28) | 1.59 (1.25, 2.03) | 1.89 (1.43, 2.50) | |
| Hot† | 0–2 | 1.15 (1.01, 1.30) | 1.21 (1.08, 1.35) | 1.04 (0.89, 1.22) | 1.21 (1.02, 1.43) | 1.26 (1.10, 1.44) |
| 0–13 | 1.25 (1.00, 1.55) | 1.32 (1.07, 1.62) | 1.04 (0.83, 1.31) | 1.59 (1.16, 2.18) | 1.34 (1.06, 1.70) | |
| 0–20 | 1.22 (0.94, 1.60) | 1.21 (0.94, 1.56) | 1.06 (0.80, 1.40) | 1.24 (0.84, 1.82) | 1.24 (0.92, 1.67) | |
*1st percentile of temperature relative to 10th percentile of temperature.
†99th percentile of temperature relative to 90th percentile of temperature; see table 1 for the percentiles of temperature.
IHD, ischaemic heart disease.