Artificial intelligence in GI endoscopy: stumbling blocks, gold standards and the role of endoscopy societies. Issue 3 (21st January 2021) - Schmitz, Rüdiger; Werner, Rene; Repici, Alessandro; Bisschops, Raf; Meining, Alexander; Zornow, Michael; Messmann, Helmut; Hassan, Cesare; Sharma, Prateek; Rösch, Thomas