2. Studies that contributed to pooled effect estimates for each non‐adverse event outcome.

Study	Overall survival	Disease‐free survival	Disease recurrence	Response/ Progression	Treatment modification/ withdrawal	Quality of Life
Ito 2004	X	X			X
Mitomi 1992	X	X	X		O
Ohwada 2004	X	X	X		X
Sadahiro 2010
Shichinohe 2013	X	X				O
Sugimoto 2012			X		X
Xu 2008	X			X		X

X: Study contributed to the effect estimate for the outcome:

O: Study reported the outcome but did not contribute to the pooled effect estimate for the outcome