They were all active duty military and largely the same socio-economic cohort, and use the same medical system. Maybe they could draw a distinction between enli

They were all active duty military and largely the same socio-economic cohort, and use the same medical system. Maybe they could draw a distinction between enlisted and commissioned, but my hunch is the disparity between raw numbers would lead to low statistical power. (This isn’t to say they originally came from the same socio-economic group, but that isn’t the type of distinction usually made in these kinds of studies.)