A recent study of a parenting program in Jamaica for highly disadvantaged children has found strong evidence for large effects on adult earnings. The study was written by a large group of researchers, including Paul Gertler, James Heckman, Rodrigo Pinto, Arianna Zanolini, Christel Vermeersch, Susan Walker, Susan Chang-Lopez, and Sally Grantham-McGregor.
Obviously the name that immediately draws attention is Nobel –prize-winning economist James Heckman, although the other researchers are also well regarded. But leaving aside research reputations, the study is well done and gets strong results. I think the study should lead to some new programs in the U.S. to see if the results can be replicated in a variety of settings.
The program targeted “stunted” children in Jamaica who on average were one and a half years old. Stunted children were those significantly below normal height for their age. This stunting is used as an indicator of malnutrition, which we know from other research will contribute to poor cognitive development. The program provided these children with services for 2 years. The services provided were nutritional supplementation, and “psychosocial stimulation”. This study and previous studies have not found strong lasting effects of the nutritional supplementation, but have found large and lasting effects of the psychosocial stimulation.
The “psychosocial simulation” consisted of weekly one-hour play visits with the child and the mother in the home by a “trained” (16 weeks of training) paraprofessional health aide. The health aides showed mothers ways to provide educational enrichment for their child through playing educational games with the child, talking to the child, and helping name objects in the child’s environment. The mother was encouraged to continue these activities throughout the week. New educational toys were provided on each visit and swapped for toys provided on previous visits.
The program evaluation is based on random assignment. There is relatively modest attrition in the original sample, and the attrition that does occur seems to be random, so the treatment and control groups seem to be truly comparable even after the attrition. The sample size is small: 53 children in the treatment group and 52 children in the control group could be located for a follow-up at age 22. But the small sample size makes it more surprising that the program could find statistically significant effects. This statistical significance only is possible because the program has such large effects on adult outcomes.
The estimate is that this the two years of weekly home visiting increased adult earnings in the program group by at least 38%. This is a very large effect. It is large enough that the program group largely “catches” up to matched “non-stunted” individuals in adult earnings. This is remarkable given that the stunted children started out with a huge malnutrition disadvantage.
Some clues to the causes of this earnings effect can be found in the pattern of other outcomes. The program significantly increased the measured quality of parenting during the two years in which services were provided, but not at later ages. Therefore, any long-term effects must reflect some special effects of improving parenting and child development during the child’s early years. The program significantly increased former child participants’ long-term educational attainment and cognitive skills, and also increased former child participants’ self-esteem while reducing anxiety and depression. The program group did NOT catch up with the non-stunted group in cognitive skills, but did catch up with the non-stunted group in educational attainment and various psychological strengths. This suggests that the earnings effect is due at least as much to improving “soft skills” as “hard skills”. Soft skills are at least as important as hard skills in improving educational attainment and adult earnings.
One aspect of this program that is striking is its time-intensity. The “psychosocial stimulation” involved 100 hours of visits over 2 years. In contrast, the home visiting program in the U.S. that is most similar to the Jamaica program, the Parent-Child Home Program, involves perhaps 50 hours of visits over 2 years. The well-known and well-evaluated Nurse Family Partnership program also involves perhaps 50 hours of home visits over a 2.5 year period (p. 98 in my Investing in Kids book provides estimates and sources). So the program seems to involve perhaps twice the time-intensity of some home visiting programs in the U.S.
In the U.S., home visiting programs have frequently shown evidence of success. The Nurse Family Partnership program has shown the strongest long-term evidence of success, but there are also favorable evaluations for other programs. However, it must be admitted that the evidence for home visiting programs in the U.S. is mixed. Not all studies find success for all programs (see pp. 11-12 of Executive Summary of October 2012 Mathematica Policy Research report for U.S. Department of Health and Human Services on home visiting program evidence). A natural question is whether greater time intensity of home visiting programs in the U.S. would lead to more consistent statistical evidence for long-term effects.
Another natural question is whether the Jamaica results can be validly extrapolated to the U.S. context. This question deserves careful experimentation and demonstration projects.
What is true is that a U.S. home visiting program on the Jamaica model could pass a benefit-cost test even if it only had a fraction of the earnings effects of the Jamaica program. In the U.S., 100 hours of home visiting would probably have less than a $10,000 two-year cost per parent and child. (Per-year costs for the Parent-Child Home program are around $2,500—see page 9 of study by Dickens and Baschnagel — and there might be economies of scale from doubling home visiting hours.) The average present value of future adult earnings for a child eligible for a free price lunch is at least $250,000. (This takes adult earnings over the child’s entire adult working career, and discounts them back to age 4. These calculations were done for my paper with Gormley and Adelstein on preschool in Tulsa. The subsidized lunch status of the child is commonly used in education research as a readily available proxy for the child being from a low income family.) With a cost of $10,000, we only need a 4% earnings effect in the U.S. for such a program to have earnings benefits that exceed costs. ($10,000=4% of $250,000). Therefore, a U.S. version of this program would only need to achieve about one-tenth of the effectiveness of the Jamaica program to pass a benefit-cost test. If the program had other benefits, such as reducing crime, the program could pass a benefit-cost test even with a smaller earnings effect.
One general lesson here is that if early childhood programs have lasting effects on adult outcomes such as earnings, they don’t have to have very large percentage effects to pay off even if the programs seem to be initially costly. Affecting an entire life course of a person has such large potential benefits that even costly interventions can make sense.
We would benefit from some additional demonstration programs and experiments with home visiting programs that might moderately ratchet up the time intensity of these programs. Two straight years of regular weekly visits might have more of an impact – or at least more of a statistically detectable impact – than less intensive interventions.
There is broad interest from across the political spectrum in programs that might help improve parenting in highly disadvantaged families. But to improve parenting probably requires programs that are both carefully designed and more intense than some people imagine. Parenting programs are not a cheap alternative to pre-K programs. Rather, as with pre-K, the key to success is good design and some minimum level of quality and intensity. But good design, quality, and time intensity all cost money. Success does not require the most intense program possible, but it does require some minimum quality level. Early childhood programs do pay off in social benefits, but they also require investments with some significant costs. In the long-run, these costs are paid for with fiscal benefits, but in the short-run there is no free lunch.