Various findings that require further research have been mentioned throughout this book. The essential case that PTSD is in fact a result of perpetration is still to be more firmly established. That it is present in certain groups and not in others needs much more clarification. The case was most strong in the group of combat veterans, since data included a large stratified random sample of veterans of a very large, long-lasting war. However, the data were cross-sectional, gathered at one point years after the war, employed self-report with no verification, and—most importantly—utilized questions not designed to actually look at whether or not PTSD can result from perpetration. In each other group, this book has simply offered a literature review upon which to base further investigation.
Matters of pattern and of implication also need extensive confirmation and expansion. There is a wide range of questions on rage, lifetime and current phases, concentration and memory problems, intrusive imagery, and a sense of personal disintegration. Do these vary across different types of groups, or with differing circumstances within groups? Do they have implications for therapy and other kinds of treatment? Are there implications for causation of symptoms? Have symptoms had social and historical impacts?
Demographic variables such as gender, race, different ethnic groups, cultures, and subcultures may prove fruitful for future research. Physical, cultural, ex-