Table 2

Diagnoses of the target lesions and observation times in each group

OutcomeWLI group
(n=2258)
2G-NBI group
(n=2265)
P value
(primary WLI vs
primary 2G-NBI)
Primary WLISecondary 2G-NBIPrimary 2G-NBISecondary WLI
Patients with EGC, n (%)44(1.9)19(0.8)53(2.3)17(0.8)0.412
Patients with a target lesion, n (%)308(13.8)114(5.0)251(11.2)124(5.5)
Target lesion, n371118282132
 EGC*, n (%)50(13.5)19(16.1)59(20.9)17(12.9)
 Others*, n (%)
 Low-grade adenoma17(4.6)7(5.9)20(7.1)2(1.6)
 Advanced gastric cancer0(0)0(0)1(0.4)0(0)
 Negative for neoplasia287(77.4)90(76.3)195(69.1)107(81.1)
 Indefinite for neoplasia1(0.3)0(0)1(0.4)1(0.8)
 Not biopsied16(4.3)2(1.7)6(2.1)5(3.8)
Positive predictive value, %13.516.120.912.90.015
Observation time†, seconds233±92254±104<0.001
  • *The common denominator of this set of values is the number of target lesions.

  • †Observation time was measured in the patients who completed the primary examination: 2234 in the WLI group and 2238 in the 2G-NBI group. Values are expressed as means±SD. An en dash represents no data collected.

  • WLI, white light imaging; 2G-NBI, second-generation narrow band imaging; EGC, early gastric cancer.