I'll try to get through the answer clearly and reasonably quickly.
We do not do elaborate screening for psychological makeup of recruits. We do ask questions about psychiatric history. By and large, if you have a significant psychiatric history, you don't get into the Canadian Forces. But we don't apply the MMPI, or any of these standardized personality-based screenings. They tried that in the Second World War and it didn't work very well. Perhaps with more research, there is some.... But you have to hit a pretty high threshold to exclude people on that basis.