Table 2.

Subgroup analysis on diagnostic accuracy of magnifying endoscopy with narrow-band imaging for the extent of early gastric cancer.

Study characteristics	Number of studies	n (lesions examined)	Events (lesions examined)	I 2	P	95% CI (%)	P value
Overall	10	1018	930	86.1%	<0.01	92.44 [86.74-96.75]
Tumor size (mm)
≤20	5	526	481	92.7%	<0.01	91.22 [78.40-98.91]	0.5728
>20	1	62	54	NA	NA	87.10 [77.45-94.46]
Depth
T1a	4	305	270	28.9%	0.24	89.28 [85.38-92.69]	0.3008
≥T1b	4	77	65	35.3%	0.20	88.82 [78.82-96.46]
Location
Upper third	6	129	113	9.0%	0.36	90.42 [82.96-96.26]	0.3678
Middle third	5	199	173	54.3%	0.07	89.94 [81.35-96.38]
Lower third	5	143	133	0	0.86	94.99 [89.85-98.67]
Macroscopic type
Elevated	3	226	213	86.0%	<0.01	92.26 [78.05-99.75]	0.9924
Flat	3	27	25	40.0%	0.19	96.21 [77.93-100.00]
Depressed	4	228	208	35.7%	0.20	94.26 [88.37-98.46]
Histological type
Differentiated	3	280	252	73.1%	0.02	92.78 [84.87-98.10]	0.6800
Undifferentiated	6	341	303	79.2%	<0.01	91.76 [82.34-98.20]
H. pylori status
Noneradicated	4	385	345	90.6%	<0.01	85.52 [70.27-96.10]	0.8187
Uninfected	3	61	56	65.4%	0.06	96.78 [75.30-100.00]
Eradicated	4	204	187	86.7%	<0.01	90.36 [74.04-99.51]
Endoscopists' experience
Less experienced	1	31	28	NA	NA	90.32 [76.92-98.70]	0.8521
Experienced	4	631	573	91.0%	<0.01	88.08 [77.38-9.577]

CI: confidence interval; T1a: mucosal cancer; T1b: submucosal cancer; NA: not available.