Same Data Set, Different Conclusions: Preschool Delay of Gratification Predicts Later Behavioral Outcomes in a Preregistered Study

One simple marshmallow test in preschool children predicts an array of important life outcomes, according to multiple studies spanning several decades. However, a recent conceptual replication casts doubt on these famous findings. We conducted an independent, preregistered secondary analysis to test whether previously observed longitudinal associations between preschool delay of gratification and adolescent outcomes would be conceptually replicated. Associations were significant for three of the five outcomes we tested using the analytic approach employed in the original studies of the marshmallow test. Relationships between delay of gratification and problem behavior held in bivariate, multivariate, and multilevel models; in contrast, no significant relationships between delay and problem behavior were found in the other recent replication, even though both studies used the same data set. These relationships were better explained by social support than by self-control, suggesting that the marshmallow test is predictive because it reflects aspects of a child's early environment that are important over the long term. This novel interpretation of the classic findings points to new directions for intervention.