Comparison of oral sodium phosphate tablets and polyethylene glycol lavage solution for colonoscopy preparation: a systematic review and meta-analysis of randomized clinical trials oleh Li Yao-dong, Li Yao-dong, Wang Yi-ping, Mai Gang, Han Yang-yun, Zhu Ling-ling, Deng Hong, Deng Jia-zheng, Xiang Rong-chao, Li You-wei, Zhao Ming, Ding Shun-bin, Ling Jing, Shen Yang, Dong Jia-qi, Deng Lei, Song Xiong-feng, Zhang You-jian, Zhou Zuo-qiong