An analysis: Colon cancer mortality in Tianjin, China, from 1981 to 2000

Table 1 Age distribution of colon cancer mortality in TianJin during 1981–2000.

Age at death	Male			Female			Total
	Death	prop (%)	rate	Death	prop (%)	rate	Death	prop (%)	rate
0-	2	0.2	0.02	2	0.2	0.02	4	0.2	0.02
20-	4	0.4	0.14	4	0.4	0.15	8	0.4	0.14
25-	15	1.4	0.43	8	0.7	0.24	23	1.1	0.34
30-	25	2.4	0.69	21	1.9	0.6	46	2.1	0.64
35-	29	2.8	0.83	23	2.1	0.67	52	2.4	0.75
40-	32	3.1	1.1	31	2.8	1.07	63	2.9	1.08
45-	48	4.6	2.1	63	5.7	2.71	111	5.2	2.41
50-	58	5.6	2.99	68	6.1	3.39	126	5.9	3.19
55-	115	11	6.53	119	10.8	6.37	234	10.9	6.4 4
60-	143	13.7	9.11	145	13.1	8.7	288	13.4	8.88
65-	166	15.9	13.27	190	17.2	14.85	356	16.6	14.05
70-	187	18	22.12	164	14.8	18.77	351	16.3	20.4
75-	139	13.4	29.31	145	13.1	27.44	284	13.2	28.29
80-	58	5.6	26.83	90	8.1	32.64	148	6.9	30.07
85-	20	1.9	22.47	33	3	21.86	53	2.5	22.07
Total	1 041	100	2.92	1 106	100	3.15	2 147	100	3.04

Prop: proportion; rate: 1/100000.

Table 2 Trend of mean age at death due to colon cancer in Tianjin, from 1981 to 2000.

Year	Male			Female			Total
	Mean	SD	SE	Mean	SD	SE	Mean	SD	SE
1981	58.7	13.94	2.2	66.31	8.48	1.22	62.85	11.85	1.26
1982	57.81	16.49	2.92	64.42	14.24	2.17	61.6	15.49	1.79
1983	59.12	11.69	1.83	64.15	14.14	1.83	62.11	13.37	1.33
1984	59.53	16.5	2.92	59	16.86	2.43	59.21	16.61	1.86
1985	62.64	12.63	1.84	61.75	16.66	2.63	62.23	14.54	1.56
1986	59.28	15.7	2.31	62.76	12.37	1.67	61.18	14.02	1.4
1987	57.63	16.24	2.4	62.49	13.36	2.14	59.86	15.1	1.64
1988	63.57	10.99	1.7	60.56	12.28	1.74	61.93	11.75	1.22
1989	61.65	14.97	2.04	62.04	15.03	2.22	61.83	14.92	1.49
1990	63.85	13.5	1.87	63.78	13.71	1.87	63.81	13.54	1.32
1991	63.39	13.04	1.73	65.75	12.06	1.91	64.36	12.63	1.28
1992	64.65	12.88	1.84	65.05	12.3	1.62	64.87	12.51	1.21
1993	67.83	10.77	1.49	64.16	13.25	1.62	65.76	12.32	1.13
1994	64.17	12.16	1.38	65.89	12.91	1.48	65.02	12.53	1.01
1995	65.13	12.85	1.56	65.07	11.2	1.5	65.1	12.09	1.09
1996	65.21	12.25	1.5	65.81	11.99	1.56	65.49	12.08	1.08
1997	64.56	14.19	1.8	69.82	12.56	1.47	67.41	13.54	1.17
1998	67.41	10.9	1.4	65.19	11.66	1.48	66.29	11.3	1.02
1999	68.06	13.44	1.67	66.29	13.51	1.63	67.15	13.45	1.16
2000	67.22	11.69	1.65	66.13	14.79	1.86	66.61	13.46	1.27
Total	63.57	13.52	0.42	64.59	13.31	0.4	64.1	13.42	0.29

Comparison of mean age at death between sexes: t = -1.75, P = 0.0796.

Table 3 Linear regression analyses for mean age at death of colon cancer.

Year of diagnosis	B	SE	STD B	t	P	95%CI
Male	0.436	0.05	0.9	8.735	0	0.331, 0.541
Female	0.237	0.06	0.683	3.97	0.001	0.112, 0.363
Total	0.336	0.042	0.882	7.943	0	0.247, 0.425

Table 4 Trend for sex ratio of colon cancer mortality in Tianjin from 1981 to 2000.

Year	Ratio	Year	Ratio	Year	Ratio	Year	Ratio
1981	0.81	1986	0.82	1991	1.4	1996	1.13
1982	0.73	1987	1.15	1992	0.83	1997	0.84
1983	0.67	1988	0.82	1993	0.77	1998	0.98
1984	0.65	1989	1.15	1994	1.01	1999	0.94
1985	1.15	1990	0.94	1995	1.2	2000	0.79

Table 5 Linear regression analyses for sex ratio of colon cancer mortality.

Variable	B	SE	STD B	t	P	95%CI
Year of diagnosis	8.86E-03	0.008	0.26	1.14	0.269	-0.007, 0.025

Table 6 Mortality rate of colon cancer in TianJin during 1981-2000.

Year	Male			Female			Total
	Deaths	Rate	ASR	Deaths	Rate	ASR	Deaths	Rate	ASR
1981	40	2.28	2.55	48	2.83	3.1	88	2.55	2.78
1982	32	2.03	2.07	43	2.78	2.81	75	2.4	2.49
1983	41	2.55	2.56	60	3.8	3.71	101	3.17	3.21
1984	32	1.95	1.93	48	2.98	2.88	80	2.46	2.43
1985	47	2.78	2.75	40	2.42	2.22	87	2.61	2.49
1986	46	2.68	2.43	55	3.28	3.04	101	2.97	2.77
1987	46	2.64	2.32	39	2.29	2.01	85	2.47	2.18
1988	42	2.37	2.08	50	2.89	2.64	92	2.63	2.36
1989	54	3.01	2.92	46	2.62	2.26	100	2.82	2.51
1990	52	2.86	2.48	54	3.03	2.49	106	2.94	2.49
1991	57	3.12	2.59	40	2.23	1.77	97	2.68	2.19
1992	49	2.67	2.3	58	3.21	2.44	107	2.94	2.35
1993	52	2.82	2.24	67	3.68	2.74	119	3.24	2.52
1994	78	4.21	3.24	76	4.15	2.98	154	4.18	3.11
1995	68	3.67	2.84	56	3.05	2.14	124	3.36	2.46
1996	67	3.62	2.64	59	3.21	2.42	126	3.41	2.53
1997	62	3.35	2.47	73	3.97	2.58	135	3.66	2.55
1998	61	3.27	2.35	62	3.35	2.19	123	3.31	2.24
1999	65	3.48	2.42	69	3.72	2.36	134	3.6	2.38
2000	50	2.66	1.77	63	3.38	2.09	113	3.02	1.92
Total	1 041	2.92	2.49	1 106	3.15	2.48	2 147	3.04	2.49

Comparison of mean mortality between sexes: χ² = 0.075 (df = 2145), P>0.05.

Table 7 Parameter estimation for linear regression of colon cancer mortality.

Year of diagnosis	B	SE	STD B	t	P	95% CI
Male	6.88E-02	0.016	0.709	4.267	0	0.035, 0.103
Female	4.29E-02	0.019	0.469	2.252	0.037	0.003, 0.083
Total	5.60E-02	0.013	0.702	4.185	0.001	0.028, 0.084