Xin Shi et al. Effect of cap-assisted esophagogastroduodenoscopy on examination of
the major duodenal papilla: a noninferior, randomized controlled trial
In a large study involving 171 patients, it was found that although complete examination
of the major duodenal papilla can be achieved by cap-assisted forward-viewing esophagogastroduodenoscopy
in most patients, it could not replace traditional duodenoscopy as the standard method
for examination.