The Rand Corporation has released a report that summarizes existing research on caregivers of veterans and lays out a blueprint for future research:

In this report, researchers describe elements of a research blueprint to inform future efforts to improve support for military and veteran caregivers… The report highlights the need for more studies that examine how military and veteran caregiver needs evolve over time, how programs are working, and how caregiving affects specific subgroups. The resulting blueprint should serve as a guide for the caregiver support community to use in prioritizing and facilitating future research.

The report can found for free on the RAND website.