Table 4

The results of seasonal multivariable analyses for OHCA using the generalised additive model with cubic splines, 2012–2016

Time	OHCA	Summer					Winter					Spring and autumn
Time	OHCA	β	t-value	RR	ER (%)	95% CI	β	t-value	RR	ER (%)	95% CI	β	t-value	RR	ER (%)	95% CI
Lag 0	Average temperature	−0.007	−1.77	0.9929	−0.71	(0.9850 to 1.0007)	−0.032	−16.90	0.9678	−3.22	(0.9640 to 0.9714)	0.011	2.39	1.0115	1.15	(1.0020 to 1.0210)
	Humidity	−0.023	−19.84	0.9769	−2.31	(0.9746 to 0.9791)	−0.002	−3.22	0.9980	−0.20	(0.9967 to 0.9992)	−0.020	−9.20	0.9798	−2.02	(0.9755 to 0.9840)
	Daily range	0.051	8.88	1.0523	5.23	(1.0404 to 1.0643)	0.007	1.99	1.0075	0.75	(1.0404 to 1.0643)	0.076	1.31	1.0799	7.99	(0.9628 to 1.2111)
	PM_2.5	0.018	21.42	1.0189	1.89	(1.0171 to 1.0206)	0.014	23.06	1.0146	1.46	(1.0133 to 1.0158)	0.022	11.76	1.0232	2.32	(1.0193 to 1.0271)
Lag 1	Average temperature	−0.011	−2.74	0.9887	−1.13	(0.9806 to 0.9967)	−0.032	−16.40	0.9682	−3.18	(0.9645 to 0.9719)	−0.006	−1.02	0.9939	−0.61	(0.9822 to 1.0056)
	Humidity	−0.024	−21.16	0.9754	−2.46	(0.9731 to 0.9776)	−0.001	−3.06	0.9980	−0.20	(0.9967 to 0.9992)	−0.020	−7.87	0.9801	−1.99	(0.9752 to 0.9850)
	Daily range	0.062	10.55	1.0642	6.42	(1.0519 to 1.0765)	0.004	1.18	1.0046	0.46	(0.9969 to 1.0123)	0.012	1.86	1.0126	1.26	(0.9993 to 1.0261)
	PM_2.5	0.019	21.74	1.0194	1.94	(1.0176 to 1.0211)	0.015	22.64	1.0153	1.53	(1.0140 to 1.0167)	0.022	9.21	1.0227	2.27	(1.0178 to 1.0275)
Lag 2	Average temperature	−0.010	−2.55	0.9896	−1.04	(0.9816 to 0.9975)	−0.032	−16.60	0.9675	−3.25	(0.9637 to 0.9713)	0.000	0.11	1.0006	0.06	(0.9899 to 1.0114)
	Humidity	−0.024	−21.01	0.9757	−2.43	(0.9735 to 0.9779)	−0.002	−4.00	0.9974	−0.26	(0.9961 to 0.9986)	−0.019	−7.86	0.9810	−1.90	(0.9763 to 0.9857)
	Daily range	0.058	9.97	1.0600	6.00	(1.0479 to 1.0722)	0.008	2.05	1.0081	0.81	(1.0003 to 1.0158)	0.060	0.95	1.0627	6.27	(0.9377 to 1.2042)
	PM_2.5	0.018	20.86	1.0184	1.84	(1.0152 to 1.0197)	0.015	23.20	1.0155	1.55	(1.0142 to 1.0168)	0.025	11.43	1.0257	2.57	(1.0212 to 1.0302)
Lag 3	Average temperature	−0.010	−2.62	0.9892	−1.08	(0.9812 to 0.9972)	−0.033	−16.54	0.9673	−3.27	(0.9634 to 0.9711)	0.002	0.43	1.0026	0.26	(0.9908 to 1.0145)
	Humidity	−0.024	−20.87	0.9754	−2.46	(0.9731 to 0.9777)	−0.002	−4.24	0.9973	−0.27	(0.9960 to 0.9985)	−0.009	−3.87	0.9905	−0.95	(0.9857 to 0.9953)
	Daily range	0.062	10.62	1.0648	6.48	(1.0525 to 1.0772)	0.006	1.54	1.0060	0.60	(0.9983 to 1.0137)	0.027	4.26	1.0274	2.74	(1.0147 to 1.0403)
	PM_2.5	0.018	21.60	1.0191	1.91	(1.0173 to 1.0208)	0.014	21.51	1.0143	1.43	(1.0129 to 1.0155)	0.021	10.39	1.0220	2.20	(1.0178 to 1.0262)
Lag 4	Average temperature	−0.003	−0.65	0.9968	−0.32	(0.9870 to 1.0065)	−0.035	−13.52	0.9648	−3.52	(0.9600 to 0.9695)	−0.009	−8.32	0.9908	−0.92	(0.9886 to 0.9929)
	Humidity	−0.014	−9.96	0.9858	−1.42	(0.9830 to 0.9885)	0.000	0.04	1.0004	0.04	(0.9987 to 1.0020)	−0.008	−17.90	0.9916	−0.84	(0.9907 to 0.9925)
	Daily range	0.013	−1.96	1.0136	1.36	(1.0000 to 1.0274)	0.007	0.75	1.0075	0.75	(0.9980 to 1.0171)	0.035	12.88	1.0357	3.57	(1.0302 to 1.0412)
	PM_2.5	0.001	1.33	1.0014	0.14	(0.9993 to 1.0034)	0.002	0.23	1.0023	0.23	(1.0007 to 1.0038)	0.002	4.11	1.0026	0.26	(1.0013 to 1.0038)
Lag 5	Average temperature	0.004	0.89	1.0044	0.44	(0.9946 to 1.0143)	−0.035	−14.16	0.9652	−3.48	(0.9605 to 0.9699)	−0.010	−9.16	0.9900	−1.00	(0.9878 to 0.9921)
	Humidity	−0.013	−9.32	0.9867	−1.33	(0.9839 to 0.9894)	0.001	1.59	1.0013	0.13	(0.9996 to 1.0029)	−0.007	−16.57	0.9923	−0.77	(0.9913 to 0.9932)
	Daily range	0.002	0.30	1.0020	0.20	(0.9890 to 1.0151)	0.003	0.80	1.0038	0.38	(0.9945 to 1.0131)	0.031	11.61	1.0316	3.16	(1.0261 to 1.0370)
	PM_2.5	0.000	0.96	1.0010	0.10	(0.9989 to 1.0029)	0.002	3.83	1.0028	0.28	(1.0013 to 1.0042)	0.001	2.13	1.0013	0.13	(1.0001 to 1.0025)
Lag 6	Average temperature	0.002	0.67	1.0020	0.20	(0.9922 to 1.0118)	−0.032	−13.15	0.9680	−3.20	(0.9632 to 0.9727)	−0.009	−8.41	0.9908	−0.92	(0.9886 to 0.9929)
	Humidity	−0.009	−8.74	0.9910	−0.90	(0.9882 to 0.9938)	0.001	1.63	1.0014	0.14	(0.9997 to 1.0030)	−0.007	−16.53	0.9924	−0.76	(0.9915 to 0.9933)
	Daily range	0.001	0.28	1.0010	0.10	(0.9880 to 1.0141)	0.006	1.31	1.0063	0.63	(0.9968 to 1.0158)	0.032	12.18	1.0328	3.28	(1.0274 to 1.0381)
	PM_2.5	0.000	0.66	1.0000	0.00	(0.9980 to 1.0020)	0.003	4.44	1.0033	0.33	(1.0018 to 1.0047)	0.001	3.06	1.0019	0.19	(1.0006 to 1.0031)

Summer (May–August), winter (December–February) and spring and autumn (March–May and September–November, respectively).
ER, excess risk; OHCA, out-of-hospital cardiac arrest; PM_2.5, particulate matter ≤2 µm; RR, relative risk.