Table 4.

IRRs of gastric cancer by follow-up period and location of ulcer

	Eradication group			Non-eradication group			IRR		IRR (sex- and age-adjusted)
	per 1000 person-years	n	Incidence	per 1000 person-years	n	Incidence		95% CI		95% CI
Overall	21.2	47	2.22	1.82	9	4.93	0.45	0.22-0.92	0.58	0.28-1.19
Follow-up period (yr)
< 1	3.77	17	4.51	0.34	2	5.81	0.78	0.18-3.33	1.16	0.27-5.00
1-3	7.48	20	2.67	0.64	4	6.27	0.43	0.15-1.25	0.50	0.17-1.49
> 3	9.92	10	1.01	0.84	3	3.56	0.28	0.08-1.03	0.34	0.09-1.28
Gastric/Gastric + duodenal ulcers	13.8	41	2.97	1.21	7	5.76	0.52	0.23-1.15	0.62	0.27-1.39
Duodenal ulcers	7.12	5	0.70	0.60	2	3.35	0.21	0.04-1.08	0.31	0.06-1.61