Additional file 1: of Crossbow needle therapy of the Miao ethnic minority group for knee osteoarthritis: study protocol for a randomized controlled trial FuJing ShangHong-cai WangLi-ying ZhaoChen CuiJin WangYan-ping 2018 SPIRIT 2013 checklist: recommended items to address in a clinical trial protocol and related documents. (DOC 119 kb)