I'm confident you're correct, rfj. I recall another student at the Kennedy School undertaking an analysis on the cost-savings of different health care interventions that we might pay for as a society. Measures that people think of as saving tons of money--smoking cessation, for example--don't pencil out. Many adult-onset interventions don't pencil out, because they allow us to live longer in retirement, spending society's wealth on our Social Security and medicare/medicaid.
Spending on kids pays off well; you don't want to invest in kids and have them depart before they start paying taxes.
There can be savings if you have a better treatment that allows someone who would otherwise be disabled and need more expensive care to be healthier and need less or no care as a consequence.