We do. I think probably the best data available is the data VAC produced in the Life After Service Studies in 2016 and 2019. There's a tremendous overlap between mental health and chronic pain.
The challenge often is that when veterans have an injury while they are in service, they're likely not going to report it because they're afraid it will impact their career, as Hélène has mentioned and as most veterans mention. I have assessed probably almost 600 veterans in the past five years, and, to a person, they have said they got injured in basic training but they didn't tell anybody because they did not want to get released. Part of the challenge is that the culture is “I'd better not disclose it because it could be the end of my career”, and sadly, that has happened to a number of them.
From VAC's own studies, there's clear evidence of the linkage between chronic pain and mental health, so you can't split the two and treat them separately. You have to treat them in one facility that deals with both.