Also one of the easier groups to target research on, since they are easier to systematically identify and are more likely to have similar underlying experiences.

And they have standardized health insurance provided through an enormous government agency, which is rare amongst workers in the US.

Right. Who has the money to pay for a study to be done? The VA, for all its faults, can. Battered women and abused IT help desk employees can't, so we don't hear stories of big expensive studies being done with them.

healthcare workers during the pandemic come to mind.