Table 4.

Stratified Estimated Mortality, Adjusted Risk, and Adjusted Relative Risk for Schizophrenia for Years 1956 Through 1965, According to Area

Year	No of cases	No of Births	Unadjusted Risk %	Estimated Mortality %	Adjusted Risk %	Adjusted RR (95% CI)a	χ2	P Value
18 Counties Surrounding Liuzhou City
1956	317	91 860	0.35	9	0.38
1957	316	105 787	0.3	12	0.34
1958	271	104 087	0.26	15	0.31
1959	257	85 742	0.3	16	0.36	1.06 (0.93–1.20)	0.73	.393
1960	253	56 467	0.45	21	0.57	1.68 (1.48–1.92)	62.66	2.460 × 10−15
1961	331	52 011	0.64	16	0.76	2.25 (2.00–2.52)	198.85	3.724 × 10−45
1962	403	130 371	0.31	10	0.34	1.02 (0.92–1.13)	0.11	.738
1963	457	160 380	0.29	8	0.31
1964	474	138 117	0.34	8	0.37
1965	491	162 805	0.3	8	0.33
1956–1958 and 1963–1965	2326	763 036	0.31	9.6	0.34	1
Liuzhou city
1956	133	9409	1.41	5	1.49
1957	141	8838	1.6	6	1.7
1958	114	9208	1.24	8	1.35
1959	129	9106	1.42	8	1.54	0.99 (0.82–1.19)	0.01	.929
1960	102	10 617	0.96	11	1.08	0.70 (0.57–0.85)	12.1	.001
1961	120	7484	1.6	8	1.74	1.12 (0.93–1.36)	1.39	.239
1962	156	12 562	1.24	5	1.31	0.84 (0.71–1.00)	3.9	.048
1963	197	13 787	1.43	4	1.49
1964	160	10 578	1.51	4	1.58
1965	152	9017	1.69	4	1.76
1956–1958 and 1963–1965	897	60 837	1.47	5	1.55	1

^aThe reference group was the years of 1956–1958 and 1963–1965.