Purpose: The Stop Now And Plan (SNAP®) model is designed to improve self-control. Extant research however, has not considered how the program targets self-control and its relation to externalizing behaviors such as aggression and rule-breaking.

Methods: This paper explores the effects of SNAP on improving self-control using the Child Behavior Checklist and Social Skills Improvement System, respectively, from a sample of 318 children. Paired samples t-tests were used to compare SSIS self-control and CBCL externalizing scores during initial and follow-up stages of treatment. Controlling for gender and age at each assessment period, a multiple linear regression was used to predict the change in externalizing behaviors based on change in self-control.

Results: Analyses further supported the effectiveness of the SNAP model by demonstrating statistically significant improvements in self-control with moderate effect sizes; this in turn predicted less externalizing behaviors.

Conclusions: The findings highlight the importance of self-control modification programs for improving self-control and reducing problem behavior.