Table 5.

PCR, rate ratio (95% CI), p-value

	PCR				PCR positive
	Rate ratio	95%CI		P-value	Rate ratio	95%CI		P-value
Years
2011	Reference				Reference
2013	2.44	0.81	7.32	0.1121	0.96	0.17	5.50	0.9645
2016	16.06	6.02	42.84	<.0001	1.54	0.29	8.23	0.6137
Regions
Hokkaido, Tohoku	5.36	0.71	40.40	0.1032	0.13	0.03	0.55	0.0051
Kanto	1.40	0.41	4.79	0.5908	0.09	0.03	0.35	0.0004
Chubu, Tokai	1.83	0.34	9.77	0.4819	0.93	0.14	6.16	0.9410
Kinki	3.68	1.10	12.26	0.0340	0.12	0.04	0.43	0.0011
Chugoku, Shikoku	3.42	0.70	16.78	0.1297	0.10	0.02	0.44	0.0022
Kyusyu, Okinawa	Reference				Reference
Units
High-volume hospitals	0.14	0.04	0.54	0.0045	10.93	2.94	40.59	0.0004
Middle- and low-volume hospitals and clinics	Reference