contains supplementary material, which is available to authorized users. Keywords Colorectal cancer I Adenoma detection rate I Adenoma miss rate I Behind folds visualizing technique I Cap-assisted colonoscopy I EndoRings I Endocuff Vision I Extra Wide Angle View (EWAVE) I Full Spectrum Endoscopy (FUSE) I Third Eye Panoramic cap I Third Eye Retroscope I Scope retroflexion I Systematic review I Meta-analysis