Table 2. The estimation of GC incidence rate in patients with GA based on subgroup analyses.

Variables			K	I2 (%)	Q test	Inc rate per 1,000 (95% CI)	Test for subgroup differences p-value*
GA
	Total		90	83.6	541.63	1.24 (0.80, 1.76)	-
	Region
		Asia	56	77.4	243.10	2.25 (1.67, 2.90)	0.454
		Europe	28	84.0	170.56	0.74 (0.13, 1.71)
		Other	6	66.3	14.82	0.00 (0.00, 0.012)
	Study design
		Prospective cohort	54	76.1	221.89	0.94 (0.48, 1.50)	<0.0001
		Retrospective cohort	32	85.4	211.88	2.72 (1.79, 3.81)
		Prospective RCT	4	0.0	2.10	0.00 (0.00, 0.001)
	Type GA
		Undetermined	46	86.6	335.18	1.57 (0.91, 2.34)	<0.0001
		GA mild	16	50.3	30.21	0.00 (0.00, 0.01)
		GA moderate	14	21.5	16.55	0.94 (0.47, 1.52)
		GA severe	14	69.1	42.02	4.82 (2.66, 7.48)
	Male (% study population)
		< 40%	7	0.0	2.64	1.60 (0.79, 2.63)	0.010
		40–50%	16	75.9	62.24	0.02 (0.00, 0.64)
		≥ 50%	45	85.8	309.52	1.48 (0.91, 2.14)
		NR	22	75.1	84.51	2.84 (1.35, 4.70)
	Age (mean, years)
		≤ 50	21	77.7	89.68	1.31 (0.52, 2.34)	0.175
		> 50	58	84.5	368.43	0.94 (0.45, 1.56)
		NR	11	80.2	50.62	3.59 (1.67, 6.09)
	Stage GC
		Advanced stage	38	81.4	198.55	3.27 (2.53, 4.10)	0.003
		Early stage	12	78.8	51.94	3.26 (1.37, 5.71)
		Undetermined	40	75.8	161.48	0.00 (0.00, 1.10)
	Follow-up time
		< 3 years	12	49.5	21.78	1.36 (0.00, 5.16)	0.330
		> 5 years	51	86.8	377.86	1.63 (1.02, 2.33)
		3–5 years	27	74.6	102.47	1.14 (0.43, 2.09)
	Endoscopy interval
		≤ 1 year	45	68.8	141.11	1.89 (1.23, 2.65)	0.053
		> 3 years	15	82.9	103.70	1.71 (0.24, 4.03)
		2–3 years	19	82.6	103.70	0.74 (0.19, 1.52)
		NR	11	86.7	75.32	0.26 (0.00, 2.32)
	Study quality
		high	38	85.1	247.72	1.63 (1.07, 2.85)	0.01
		moderate	52	74.6	200.81	1.20 (0.56, 2.02)

*Test for subgroup differences (random effects model)

K, number of study; Inc, incidence; GA, gastric atrophy; GC, gastric cancer.