Table 2.

The Poisson regression model for associations between case-severity rate and city-specific characteristics

Variables	Estimate	SE	t	P value	RR (95%CI) b	RR (95%CI) a
Population increase rate	0.104	0.175	0.595	0.553	1.109 (0.788, 1.562)	1.024 (0.718, 1.459)
Population density	− 0.026	0.100	− 0.261	0.795	0.974 (0.801, 1.186)	1.041 (0.820, 1.323)
GDP increase rate	− 0.294	0.112	− 2.635	0.009	0.745 (0.599, 0.927)	0.921 (0.777, 1.092)
Per capita public green areas	− 0.105	0.077	− 1.362	0.175	0.901 (0.775, 1.047)	0.868 (0.751, 1.003)
City development	− 0.195	0.055	− 3.561	< 0.001	0.823 (0.739, 0.916)	0.893 (0.821, 0.970)
Meteorological feature	− 0.261	0.112	− 2.321	0.022	0.771 (0.619, 0.960)	0.723 (0.592, 0.882)
Intercept	− 4.666	0.137	− 33.952	< 0.001	0.009 (0.007, 0.012)	–

^aThe crude RR for case-severity rate

^bThe adjusted RR in multivariate Poisson regression