Office stocking has proceeded to the point where I can catch up on some reading. Science from August 19 includes a special section devoted to Investing in Early Education. The ten articles present compelling data regarding the efficacy of preschool. By the 1980s early education had enough documented benefits that randomized controlled trials were deemed impossible (because parents would refuse to be in the control group) or unethical (because effective "therapies" would be withheld), leading to a case-control design for the first large longitudinal study.
I encourage you to read the whole section; it's worth it, even if you have to pay!
The first article in particular asks a major question: why isn't early education offered to all children who need it, given its documented benefits? Three long-running studies are reviewed, all of which demonstrate significant benefits well into adult life (see figure).
HighScope/Perry first demonstrated the benefits of early learning in 123 students with a return on investment of $16 for every dollar spent. The intervention cost almost $18,000 per student for half-day attendance during the school year. Subsequently, the Abecedarian study also used a randomized control design from age 6 weeks to 5 years with full-day year round classes. Costs rose appreciably to just over $70,000 per subject; ROI dropped to $2.5 per dollar invested.
The Chicago study did not boast a randomized design, but did involve 1,539 students at a cost of only $8,224 per student for half-day, school year programs. Each dollar spent produced $10 of benefits over time. Sounds like this one hit a sweet spot in terms of "bang for the buck."
What benefits are we measuring? Graduating from high school, better employment, and lower incarceration rates. All of these factors also correlate with better health.
So why don't we have universal preschool, at least for high risk children? We have lots of data showing benefit and excellent ROI for society! A variety of issues come into play.
The nature of "at risk children" changes over time. At present, many more immigrant, English-as-second-language children are in the US than in these earlier studies. Will similar programs translate to these youth? Only time and tracking will tell. While I tend to err on the side of intervention (I mean, do we really think it would hurt?), those who control the funds often come out on the other end of the equation (we can do nothing till we know what works!). Now we also must contend with those who believe only stay-at-home-mommies are the answer. Which brings us to politics.
And that's the real issue. Children do not vote. These programs primarily help bridge the gap between advantaged and disadvantaged kids; those who fund political campaigns generally do not look for this sort of extremely long-term return on investment. Even though we would all be better off with better educated, skilled workers who stay out of jail (thus providing the labor force and tax base we need for our society and economy to thrive), many in the US consider this unnecessary spending.
If we withheld a treatment this effective in the practice of medicine, it would be criminal.
One could argue the same in this situation.