“…As such, they are preeminently suited to the detection of treatment-subgroup interactions. Several tree-based algorithms for the detection of treatment-subgroup interactions have already been developed (Dusseldorp, Doove, & Van Mechelen, 2016;Dusseldorp & Meulman, 2004;Su, Tsai, Wang, Nickerson, & Li, 2009;Foster, Taylor, & Ruberg, 2011;Lipkovich, Dmitrienko, Denne, & Enas, 2011;Zeileis, Hothorn, & Hornik, 2008;Seibold, Zeileis, & Hothorn, 2016;Athey & Imbens 2016). Also, Zhang, Tsiatis, Laber, and Davidian (2012b) and Zhang, Tsiatis, Davidian, Zhang, and Laber (2012a) have developed a flexible classification-based approach, allowing users to select from a range of statistical methods, including trees.…”