Acupuncture versus massage for pain in patients living with advanced cancer: a protocol for the IMPACT randomised clinical trial oleh Han Xiao, Katherine Panageas, Jun J Mao, Kevin Liou, Sally A D Romero, Nicholas Emard, Raymond E Baser, Jodi MacLeod, Desiree Walker, Margaret Barton-Burke, Gary Deng, John Farrar, Andrew Epstein