Can a propensity score matching method be applied to assessing efficacy from single‐arm proof‐of‐concept trials in oncology? oleh Shu‐Wen Teng, Yu‐Cheng Su, Ravikumar Pallantla, Madhav Channavazzala, Rukmini Kumar, Yucheng Sheng, Hao Wang, Crystal Wang, Archie Tse