On 2016 May 07, Jan Preiss commented:

I was a little bit surprised to see that the NBI mode in the study by Leung et al. an endoscope from the 190 series was compared to the white light mode in an endoscope from the 260 series. Having worked with both types of endoscopes I find even the white light picture in the 190 series a lot sharper and brighter than any of the older Olympus endoscopes - including the 260/160 series. It is very difficult to conclude from this design whether the higher adenoma detection rate actually stems from using the NBI mode or merely from using an endoscope with superior light and optics.

On 2016 May 07, Jan Preiss commented:

I was a little bit surprised to see that the NBI mode in the study by Leung et al. an endoscope from the 190 series was compared to the white light mode in an endoscope from the 260 series. Having worked with both types of endoscopes I find even the white light picture in the 190 series a lot sharper and brighter than any of the older Olympus endoscopes - including the 260/160 series. It is very difficult to conclude from this design whether the higher adenoma detection rate actually stems from using the NBI mode or merely from using an endoscope with superior light and optics.