Delay of gratification and adult outcomes: The Marshmallow Test does not reliably predict adult functioning

Sperber, J. F., et al. (2024).

Child Development.

https://doi.org/10.1111/cdev.14129

Abstract

This study extends the analytic approach conducted by Watts et al. (2018) to examine the long-term predictive validity of delay of gratification. Participants (n = 702; 83% White, 46% male) completed the Marshmallow Test at 54 months (1995–1996) and survey measures at age 26 (2017–2018). Using a preregistered analysis, Marshmallow Test performance was not strongly predictive of adult achievement, health, or behavior. Although modest bivariate associations were detected with educational attainment (r = .17) and body mass index (r = −.17), almost all regression-adjusted coefficients were nonsignificant. No clear pattern of moderation was detected between delay of gratification and either socioeconomic status or sex. Results indicate that Marshmallow Test performance does not reliably predict adult outcomes. The predictive and construct validity of the ability to delay of gratification are discussed.

A pdf of the research is here.

Here are some thoughts:

This study is part of the replication crisis in psychology. This study examined the long-term predictive validity of the Marshmallow Test, a widely used measure of delay of gratification. The test, administered to 702 participants at age 4, was found to have limited predictive power for adult outcomes, such as achievement, health, and behavior, at age 26. While modest associations were detected with educational attainment and body mass index, these correlations were largely explained by demographics and home life factors. The study's findings question the construct validity of the Marshmallow Test, suggesting it may not accurately measure delay of gratification. Instead, it may screen for broader developmental advantages in early childhood. These results have implications for intervention strategies, highlighting the need to focus on broader capacities for lasting impact.

Why Rich Kids Are So Good at the Marshmallow Test

Jessica McCrory Calarco
The Atlantic
Originally published June 1, 2018

Here is an excerpt:

This new paper found that among kids whose mothers had a college degree, those who waited for a second marshmallow did no better in the long run—in terms of standardized test scores and mothers’ reports of their children’s behavior—than those who dug right in. Similarly, among kids whose mothers did not have college degrees, those who waited did no better than those who gave in to temptation, once other factors like household income and the child’s home environment at age 3 (evaluated according to a standard research measure that notes, for instance, the number of books that researchers observed in the home and how responsive mothers were to their children in the researchers’ presence) were taken into account. For those kids, self-control alone couldn’t overcome economic and social disadvantages.

The failed replication of the marshmallow test does more than just debunk the earlier notion; it suggests other possible explanations for why poorer kids would be less motivated to wait for that second marshmallow. For them, daily life holds fewer guarantees: There might be food in the pantry today, but there might not be tomorrow, so there is a risk that comes with waiting. And even if their parents promise to buy more of a certain food, sometimes that promise gets broken out of financial necessity.

The information is here.