The interpersonal whole-brain model of care®: A pilot study comparing outcomes between established and first-year affiliate sites

Abstract

This study examines whether the Interpersonal Whole-Brain Model of Care® (IWBMC™) produces consistent outcomes across implementation sites of differing maturity, comparing an established site with newer affiliates. Developed over 30 years at the Jacob’s Ladder School, the IWBMC is a comprehensive approach to neurodevelopmental intervention that integrates seven interconnected elements grounded in interpersonal neurobiology. We conducted a retrospective pilot study of 16 participants (Ages 3.5-14.9) who received at least 6 months of programming, analyzing pre-post change with paired-samples t-tests(Cohen’s d, 95% confidence intervals) and between-site differences with independent-samples t-tests on change scores. Significant improvements emerged across multiple neurodevelopmental, cognitive, and academic domains, including auditory, visual, and manual function; language; mobility; sequential processing; and word reading, with medium-to-large effect sizes; primitive reflex integration showed the largest gain. No between-site difference reached significance, consistent with model transfer; however, the study was underpowered (n = 8 per site), and several point estimates favored the established site, so equivalence cannot be concluded. Because of the small sample, these findings are preliminary and cannot support causal or psychometric conclusions. Nonetheless, they suggest that the IWBMC may be scalable across settings, and they provide a foundation for larger prospective validation studies to establish its psychometric properties and confirm its transferability across diverse implementation contexts.