“…Nonetheless, several authors recommended increasing research on the effects of participation in trauma research [23,26,30,31,74,75,77,80,81,118,152] as well as educating IRBs on the possible benefits of trauma-focused research [23,77,80]. Articles on methodology concerned sampling and data collection [153][154][155][156], a need to use consistent measures and not conflate different constructs [123,127,128], a need to see participants as potentially being both survivors and perpetrators of violence [122], and the nocebo effect in trauma research [119]. Researchers offered recommendations on improving internal research validity when potential control group members with trauma do not identify themselves as having trauma [31,121], and many recommended using participatory research methods to conduct better research [132,135,137,138,155].…”