I just finished Michael Marmot's The Health Gap and he discusses how ACEs and Education are both important in health outcomes.
Actual cost-benefit studies are important.
As to why, but as it applies to primary care, there's also the recent study of Porcerelli et al (May this year) doi: 10.1177/0091217417730290
Again, the same old problem -- studying only the effects of childhood physical and sexual abuse rather than a broader range of ACEs -- weakens the study imho.
Of course, learning from other studies, such cost-benefit studies would need to be longitudinal in nature, and broad ranging in measuring outcomes -- as short term interventions might lead to no reduction in use of medical services (although perhaps reduced emergency services). From the abstract: "Findings revealed that adult patients with histories of childhood abuse generally scored significantly higher on measures of psychopathology, emergency room use, and doctorâpatient relationship difficulty, and lower on a measure of mental and physician-rated physical health."
Also, whilst it might be more palatable, it's important to remember, which Marmot seems to not, is that his conclusion "the higher the social status of individuals, the better their health." is not clear cut -- as the original ACEs studies demonstrate, ACEs are not a respecter of social status. Irrespective of the social status of the patient " It is especially important for physicians to routinely include an assessment of childhood abuse during the psychosocial portion of the medical interview or through screening instruments."